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The Red October gold mine, in an Archaean granite-greenstone deposit, is a relatively young deposit in terms of developed structural and genetic models. The most important regional deformation events were D4b (WNW-ESE sinistral transpression) and D5 (ENE-WSW dextral transpression), which have been attributed to the main Au mineralising phases. Fully coupled 3D finite element analysis showed anomalous patterns of stress and strain and subsequent fluid flow as a result of the two main deformation events. The D4 simulation provided a good correlation with the known distribution of subsidiary structures on the main shear zone, and also provided several geomechanical targets that suggested locations of additional subsidiary structures. The D5 simulation provided insight into the response of the main shear zone and known subsidiary structures, also highlighting additional targets for further mineralisation. These targets have been followed up with a 732 m deep surface reverse circulation drill hole, resulting in the discovery of two high-grade shoots., The Red October gold mine, in an Archaean granite-greenstone deposit, is a relatively young deposit in terms of developed structural and genetic models. The most important regional deformation events were D4b (WNW-ESE sinistral transpression) and D5 (ENE-WSW dextral transpression), which have been attributed to the main Au mineralising phases. Fully coupled 3D finite element analysis showed anomalous patterns of stress and strain and subsequent fluid flow as a result of the two main deformation events. The D4 simulation provided a good correlation with the known distribution of subsidiary structures on the main shear zone, and also provided several geomechanical targets that suggested locations of additional subsidiary structures. The D5 simulation provided insight into the response of the main shear zone and known subsidiary structures, also highlighting additional targets for further mineralisation. These targets have been followed up with a 732 m deep surface reverse circulation drill hole, resulting in the discovery of two high-grade shoots.

The 335 000 oz Wilber deposit is located within the Meekatharra-Wydgee Archaean greenstone belt in the Murchison District of Western Australia. The deposit comprises high-grade gold mineralisation hosted within a steeply west-dipping quartz lode, which lies within a north-east striking shear zone. The entire mine area is cross-cut by a system of shallow barren quartz veins. The north-east-trending lode lies within a 3 m wide shear zone and varies from a 0.5-4 m wide laminated, massive or brecciated quartz-carbonate vein to multiple laminated veins up to 1 m wide within the shear. Mineralisation occurs as free gold within the quartz carbonate veins, with accessory sulphides including pyrite, chalcopyrite, galena and sphalerite. Gold grades range from less than 1 g/t within the hosting shear zone to around 30 g/t in the single vein, and up to more than 60 g/t in the multiple vein areas. Gold is commonly visible and disseminated throughout laminated, breccia and massive quartz veins. Open pit mining began in November 2012 and gold recovery rates of 99% at 10 g/t head grade have been achieved., The 335 000 oz Wilber deposit is located within the Meekatharra-Wydgee Archaean greenstone belt in the Murchison District of Western Australia. The deposit comprises high-grade gold mineralisation hosted within a steeply west-dipping quartz lode, which lies within a north-east striking shear zone. The entire mine area is cross-cut by a system of shallow barren quartz veins. The north-east-trending lode lies within a 3 m wide shear zone and varies from a 0.5-4 m wide laminated, massive or brecciated quartz-carbonate vein to multiple laminated veins up to 1 m wide within the shear. Mineralisation occurs as free gold within the quartz carbonate veins, with accessory sulphides including pyrite, chalcopyrite, galena and sphalerite. Gold grades range from less than 1 g/t within the hosting shear zone to around 30 g/t in the single vein, and up to more than 60 g/t in the multiple vein areas. Gold is commonly visible and disseminated throughout laminated, breccia and massive quartz veins. Open pit mining began in November 2012 and gold recovery rates of 99% at 10 g/t head grade have been achieved.

About 32% of global Au production has come from greenstone belts where numerous small to large, quartz vein-associated deposits are hosted in metamorphic rocks ranging from lower greenschist to granulite facies. Historical exploration has focused on rocks of greenschist to lower amphibolite facies as these seem to contain the most deposits, and these regions are now reaching mature brownfield status, particularly in developed nations, and finding new deposits is becoming progressively more difficult. Regions of similar tectonic setting but containing high-grade metamorphic rocks of mid-amphibolite to granulite facies have received little attention because the first explorers found fewer deposits there. These regions do however contain significant Au deposits such as Hemlo in Canada with about 684 t of Au, Renco in Zimbabwe where about 31 t of Au has been mined since 1980, the Challenger deposit in South Australia with 36 t of Au recovered + reserve + resource and the Tropicana deposit in Western Australia with about 182 t of Au reserve + resource. High-grade metamorphic terrains offer explorers an excellent opportunity to move onto relatively green fields within developed nations, which carry less risk associated with development. Based on consideration of the characteristics of Au deposits hosted in high-grade metamorphic rocks, two categories are defined, deposits which formed prior to peak metamorphism and deposits that formed well after peak metamorphism. No deposits have been convincingly been shown to have formed during peak metamorphism. Exploration should focus on old structures that have been metamorphosed and probably deformed by folding or reactivated. In these settings, Au occurs in unusual metamorphic rocks characterised by low-Fe silicate assemblages. Metamorphosed deposits are likely to be highly deformed, with complex orebody geometries. Where granulite facies terranes have been thrust over rocks over lower metamorphic grade, there is potential for f, About 32% of global Au production has come from greenstone belts where numerous small to large, quartz vein-associated deposits are hosted in metamorphic rocks ranging from lower greenschist to granulite facies. Historical exploration has focused on rocks of greenschist to lower amphibolite facies as these seem to contain the most deposits, and these regions are now reaching mature brownfield status, particularly in developed nations, and finding new deposits is becoming progressively more difficult. Regions of similar tectonic setting but containing high-grade metamorphic rocks of mid-amphibolite to granulite facies have received little attention because the first explorers found fewer deposits there. These regions do however contain significant Au deposits such as Hemlo in Canada with about 684 t of Au, Renco in Zimbabwe where about 31 t of Au has been mined since 1980, the Challenger deposit in South Australia with 36 t of Au recovered + reserve + resource and the Tropicana deposit in Western Australia with about 182 t of Au reserve + resource. High-grade metamorphic terrains offer explorers an excellent opportunity to move onto relatively green fields within developed nations, which carry less risk associated with development. Based on consideration of the characteristics of Au deposits hosted in high-grade metamorphic rocks, two categories are defined, deposits which formed prior to peak metamorphism and deposits that formed well after peak metamorphism. No deposits have been convincingly been shown to have formed during peak metamorphism. Exploration should focus on old structures that have been metamorphosed and probably deformed by folding or reactivated. In these settings, Au occurs in unusual metamorphic rocks characterised by low-Fe silicate assemblages. Metamorphosed deposits are likely to be highly deformed, with complex orebody geometries. Where granulite facies terranes have been thrust over rocks over lower metamorphic grade, there is potential for f

The Weld Range greenstone belt, in the Murchison Domain of the Yilgarn Craton, hosts two Archaean high-grade deposits, Madoonga (68 000 000 t at 57.7 wt% Fe) and Beebyn (62 000 000 t at 59.6 wt% Fe, ASX announcement 2008). Five main types of high-grade (more than 55 wt% Fe) iron mineralisation each display characteristic grades, tonnage and contaminant levels, which affect exploration strategies and beneficiation methods: residual ore formed as a result of two generations of hypogene alteration of banded iron formation (BIF), the first alteration phase replacing silica-rich bands with siderite and/or Fe-rich dolomite and the second phase removing carbonate gangue minerals and concentrating residual Fe oxide-rich bands in the BIF via volume reduction; the product is a high-grade, high-tonnage Fe orebody, with minor contaminants. Magnetite-bearing shear and fault zones that cut the BIF along lithological contacts formed as a result of the addition of hypogene magnetite via the circulation of Fe-rich, hypogene hydrothermal fluids through BIF, which produced low-tonnage, high-grade magnetite-rich ore zones whose high levels of contaminants such as SiO2 and Al2O3 result from the difficulty of mining these zones. Specular haematite- +/-quartz-bearing shear and fault zones that cut residual orebodies and magnetite-bearing structures share similar characteristics to those of the magnetite-bearing structures. Goethite-haematite supergene ore zones are controlled by brittle faults cutting the BIF that promoted the flow of supergene fluids through the BIF and resulted in large ore zones with variable Fe grades and contaminants. Detrital deposits comprise transported BIF fragments and are intensely goethite-haematite supergene-altered; these orebodies are locally extensive, with moderate Fe grades., The Weld Range greenstone belt, in the Murchison Domain of the Yilgarn Craton, hosts two Archaean high-grade deposits, Madoonga (68 000 000 t at 57.7 wt% Fe) and Beebyn (62 000 000 t at 59.6 wt% Fe, ASX announcement 2008). Five main types of high-grade (more than 55 wt% Fe) iron mineralisation each display characteristic grades, tonnage and contaminant levels, which affect exploration strategies and beneficiation methods: residual ore formed as a result of two generations of hypogene alteration of banded iron formation (BIF), the first alteration phase replacing silica-rich bands with siderite and/or Fe-rich dolomite and the second phase removing carbonate gangue minerals and concentrating residual Fe oxide-rich bands in the BIF via volume reduction; the product is a high-grade, high-tonnage Fe orebody, with minor contaminants. Magnetite-bearing shear and fault zones that cut the BIF along lithological contacts formed as a result of the addition of hypogene magnetite via the circulation of Fe-rich, hypogene hydrothermal fluids through BIF, which produced low-tonnage, high-grade magnetite-rich ore zones whose high levels of contaminants such as SiO2 and Al2O3 result from the difficulty of mining these zones. Specular haematite- +/-quartz-bearing shear and fault zones that cut residual orebodies and magnetite-bearing structures share similar characteristics to those of the magnetite-bearing structures. Goethite-haematite supergene ore zones are controlled by brittle faults cutting the BIF that promoted the flow of supergene fluids through the BIF and resulted in large ore zones with variable Fe grades and contaminants. Detrital deposits comprise transported BIF fragments and are intensely goethite-haematite supergene-altered; these orebodies are locally extensive, with moderate Fe grades.

The Carina deposit was discovered in May 2007 and is located within and parallel to the structurally complex NW-trending Mount Dimer shear zone. The volcanosedimentary Archaean-aged greenstone sequence consists of ultramafic and mafic lavas and flows with interbedded sediments, dominated by chert and banded iron formation (BIF). Supergene enrichment processes formed a goethite orebody replacement of BIF sequences within a doubly plunging synclinal fold structure. Mineralised outcrops dominated by goethite form a low ridge 1 500 m long, up to 90 m wide and drilled to over 200 m in depth. Iron occurrences have been identified over at least a 12 km strike length in the vicinity of the deposit. The mineralisation is predominantly goethite with specular and coarse platy haematite localised along structures that cut the goethite mineralisation. Mineralised zones are moderately vuggy and larger cavities occur in proximity to fault zones that transect the orebody. The inferred resource is 27 900 000 t at 58.6% Fe, 1.3% Al2O3, 3.7% SiO2, 0.09% P and 10.1% LOI., The Carina deposit was discovered in May 2007 and is located within and parallel to the structurally complex NW-trending Mount Dimer shear zone. The volcanosedimentary Archaean-aged greenstone sequence consists of ultramafic and mafic lavas and flows with interbedded sediments, dominated by chert and banded iron formation (BIF). Supergene enrichment processes formed a goethite orebody replacement of BIF sequences within a doubly plunging synclinal fold structure. Mineralised outcrops dominated by goethite form a low ridge 1 500 m long, up to 90 m wide and drilled to over 200 m in depth. Iron occurrences have been identified over at least a 12 km strike length in the vicinity of the deposit. The mineralisation is predominantly goethite with specular and coarse platy haematite localised along structures that cut the goethite mineralisation. Mineralised zones are moderately vuggy and larger cavities occur in proximity to fault zones that transect the orebody. The inferred resource is 27 900 000 t at 58.6% Fe, 1.3% Al2O3, 3.7% SiO2, 0.09% P and 10.1% LOI.

The Grao Para and Rio Maria greenstone banded iron formations (BIFs) exhibit distinct lithological and petrographic fabrics, together with pronounced differences in their surface expression, real thickness, iron grade and tonnage, which support a new model for the regional distribution of iron formations in the Carajas province. The Carajas Formation of the Grao Para Group is the main economic iron formation, with regard to grade and tonnage. The iron ore content in the Rio Maria greenstone BIFs is strongly modified by a metamorphic fabric., The Grao Para and Rio Maria greenstone banded iron formations (BIFs) exhibit distinct lithological and petrographic fabrics, together with pronounced differences in their surface expression, real thickness, iron grade and tonnage, which support a new model for the regional distribution of iron formations in the Carajas province. The Carajas Formation of the Grao Para Group is the main economic iron formation, with regard to grade and tonnage. The iron ore content in the Rio Maria greenstone BIFs is strongly modified by a metamorphic fabric.

Barrack Gold Corporation's Buzwagi Mine is located in the Lake Victoria greenstone belt district of Tanzania. The orebody occurs in the Nzega Shear zone within the greenstone belt and is hosted in a K-feldspar-rich granite in contact with mafic volcanic rocks. The orebody holds 2 600 000 ounces of gold in a reserve of 41 000 000 tonnes at 2.0 g/t, with an estimated mine life of 10 years. The prefeasibility study was completed by SNC-Lavalin in 2006, and showed that the two major challenges were grade control and the effect of dilution. The paper describes the mine planning methodology used, the net smelter revenue calculation and the effects of cut-off grades on project economics and mine scheduling., Barrack Gold Corporation's Buzwagi Mine is located in the Lake Victoria greenstone belt district of Tanzania. The orebody occurs in the Nzega Shear zone within the greenstone belt and is hosted in a K-feldspar-rich granite in contact with mafic volcanic rocks. The orebody holds 2 600 000 ounces of gold in a reserve of 41 000 000 tonnes at 2.0 g/t, with an estimated mine life of 10 years. The prefeasibility study was completed by SNC-Lavalin in 2006, and showed that the two major challenges were grade control and the effect of dilution. The paper describes the mine planning methodology used, the net smelter revenue calculation and the effects of cut-off grades on project economics and mine scheduling.

Most gold in eastern China comes from the East Shandong, North China and Xiaoqinling gold provinces, with a minor amount found in SE China. These provinces represent the northern and south-eastern margins of the North China (Sino-Korean) block, the high-pressure suture zone between the North and South China blocks, the fold belts between the North China and Yangtze blocks and the SE China fold belt. A quarter of Chinese gold reserves are hosted by rocks in eastern Shandong, which produces some 750 000-1 000 000 oz/a Au from quartz-vein and shear-zone deposits hosted by granites and Archaean metamorphic rocks. The North China province, in Inner Mongolia, Hebei, Liaoning and Jilin, has resources of 25 000 000-30 000 000 oz Au scattered over a much larger area and contained in greenstone- and granite-hosted deposits. Henan and Shaanxi have over 15 000 000 oz Au in large quartz veins hosted by Archaean and Lower Proterozoic metamorphic rocks and greenstone belts., Most gold in eastern China comes from the East Shandong, North China and Xiaoqinling gold provinces, with a minor amount found in SE China. These provinces represent the northern and south-eastern margins of the North China (Sino-Korean) block, the high-pressure suture zone between the North and South China blocks, the fold belts between the North China and Yangtze blocks and the SE China fold belt. A quarter of Chinese gold reserves are hosted by rocks in eastern Shandong, which produces some 750 000-1 000 000 oz/a Au from quartz-vein and shear-zone deposits hosted by granites and Archaean metamorphic rocks. The North China province, in Inner Mongolia, Hebei, Liaoning and Jilin, has resources of 25 000 000-30 000 000 oz Au scattered over a much larger area and contained in greenstone- and granite-hosted deposits. Henan and Shaanxi have over 15 000 000 oz Au in large quartz veins hosted by Archaean and Lower Proterozoic metamorphic rocks and greenstone belts.

Both disseminated and massive nickel sulphide deposits are present within the deformed and metamorphosed Honeymoon Well ultramafic complex in Western Australia. The ultramafic sequence consists of a diverse suite of metamorphosed komatiites including spinifex-textured rocks, olivine orthocumulates, mesocumulates and adcumulates. The distinctly different komatiitic rock types reflect formation in markedly different volcanic settings. Disseminated ores occur at the Hannibals, Harrier and Corella deposits and massive sulphides at the Wedgetail deposit. At December 1995 indicated resources were 155 500 000 t at 0.71% nickel in four main deposits, including a massive sulphide resource of 2 500 000 t at 3.4% nickel., Both disseminated and massive nickel sulphide deposits are present within the deformed and metamorphosed Honeymoon Well ultramafic complex in Western Australia. The ultramafic sequence consists of a diverse suite of metamorphosed komatiites including spinifex-textured rocks, olivine orthocumulates, mesocumulates and adcumulates. The distinctly different komatiitic rock types reflect formation in markedly different volcanic settings. Disseminated ores occur at the Hannibals, Harrier and Corella deposits and massive sulphides at the Wedgetail deposit. At December 1995 indicated resources were 155 500 000 t at 0.71% nickel in four main deposits, including a massive sulphide resource of 2 500 000 t at 3.4% nickel.

The deposits, in Western Australia, occur in a massive granite in the footwall of the Dimer lag, a regional scale structural zone forming the southern margin of the Archaean Marda greenstone belt. Four principal lode gold deposits and several minor laterite deposits have been mined within the area, and several lode structures are currently being evaluated. Mineralisation is contained in elongate shoots associated with the development of foliation-parallel laminated quartz-sulphide veins and locally veins of massive sulphide, and screens of altered wall rock within the otherwise narrow lode structure. During the year to June 30 1996, 33 136 oz of Au and 50 946 oz of Ag were produced from 175 702 t of ore. Remaining proved and probable reserves are 165 280 t of ore at 7.1 g/t Au., The deposits, in Western Australia, occur in a massive granite in the footwall of the Dimer lag, a regional scale structural zone forming the southern margin of the Archaean Marda greenstone belt. Four principal lode gold deposits and several minor laterite deposits have been mined within the area, and several lode structures are currently being evaluated. Mineralisation is contained in elongate shoots associated with the development of foliation-parallel laminated quartz-sulphide veins and locally veins of massive sulphide, and screens of altered wall rock within the otherwise narrow lode structure. During the year to June 30 1996, 33 136 oz of Au and 50 946 oz of Ag were produced from 175 702 t of ore. Remaining proved and probable reserves are 165 280 t of ore at 7.1 g/t Au.

The deposits, in Western Australia, are blind deposits occurring in a sequence of mafic, ultramafic and sedimentary rocks within the Norseman-Wiluna greenstone belt. Gold mineralisation is associated with the Zuleika shear zone and occurs mainly within sheared and altered silicified zones, and in quartz stockworks developed in quartz dolerite sills and occasionally within silicified ultramafic rock and metasediment. Due to intense weathering the primary mineralisation has undergone strong near-surface depletion. Structural controls on mineralisation were the shear zone, the presence of structurally brittle and chemically receptive quartz dolerite host rocks and their competency contrast with the enveloping metasediment and ultramafic rocks. To the end of 1993 a total of 697 000 t of open pit ore averaging 4.13 g/t Au had been treated, with a further 350 000 t of low- and sub-grade ore stockpiled., The deposits, in Western Australia, are blind deposits occurring in a sequence of mafic, ultramafic and sedimentary rocks within the Norseman-Wiluna greenstone belt. Gold mineralisation is associated with the Zuleika shear zone and occurs mainly within sheared and altered silicified zones, and in quartz stockworks developed in quartz dolerite sills and occasionally within silicified ultramafic rock and metasediment. Due to intense weathering the primary mineralisation has undergone strong near-surface depletion. Structural controls on mineralisation were the shear zone, the presence of structurally brittle and chemically receptive quartz dolerite host rocks and their competency contrast with the enveloping metasediment and ultramafic rocks. To the end of 1993 a total of 697 000 t of open pit ore averaging 4.13 g/t Au had been treated, with a further 350 000 t of low- and sub-grade ore stockpiled.

The deposits, in Western Australia, are hosted by a structurally prepared sequence of sedimentary, volcaniclastic, mafic and ultramafic volcanic and intrusive rocks typical of Archaean greenstone sequences. Gold mineralisation is in the form of thin and planar laminated quartz veins less than 2 m thick which occur along or near at least three distinct rock unit contacts. The wall rocks exhibit strong localised shearing and alteration but have negligible gold content. The veins contain free gold with trace sulphides. Secondary supergene mineralisation has developed variably near surface. There are five main orebodies: the South and North lodes, Strzelecki, Barkers and the 21 Mile orebody. Mining of the first of a number of open pits began in 1988 and production to July 1996 was 2 569 000 t at 4.8 g/t gold. Remaining proved and probable reserves are 2 805 000 t at 7.6 g/t gold., The deposits, in Western Australia, are hosted by a structurally prepared sequence of sedimentary, volcaniclastic, mafic and ultramafic volcanic and intrusive rocks typical of Archaean greenstone sequences. Gold mineralisation is in the form of thin and planar laminated quartz veins less than 2 m thick which occur along or near at least three distinct rock unit contacts. The wall rocks exhibit strong localised shearing and alteration but have negligible gold content. The veins contain free gold with trace sulphides. Secondary supergene mineralisation has developed variably near surface. There are five main orebodies: the South and North lodes, Strzelecki, Barkers and the 21 Mile orebody. Mining of the first of a number of open pits began in 1988 and production to July 1996 was 2 569 000 t at 4.8 g/t gold. Remaining proved and probable reserves are 2 805 000 t at 7.6 g/t gold.

The deposit, in Western Australia, is hosted by the Archaean Black Flag sedimentary sequence of epiclastic rocks with interlayered felsic volcanogenic rocks. Mineralisation is in lodes of quartz-veined and silicified quartzo-feldspathic schist with less than 5% pyrite. Supergene alteration of lode minerals extends for at least 100 m vertically below the top of the weathered bed rock. The deposit is completely concealed beneath younger sediment. At December 1994, the measured resource to 150 m depth was 2 500 000 t grading 2.7 g/t gold., The deposit, in Western Australia, is hosted by the Archaean Black Flag sedimentary sequence of epiclastic rocks with interlayered felsic volcanogenic rocks. Mineralisation is in lodes of quartz-veined and silicified quartzo-feldspathic schist with less than 5% pyrite. Supergene alteration of lode minerals extends for at least 100 m vertically below the top of the weathered bed rock. The deposit is completely concealed beneath younger sediment. At December 1994, the measured resource to 150 m depth was 2 500 000 t grading 2.7 g/t gold.

The deposit, in Western Australia, is a recent discovery in an area of thick transported overburden and deep weathering. The main rock types are komatiite flows and intrusions, high-Mg and tholeiitic basalt and dolerite, intermediate to felsic volcanic rocks, internal granitoid plutons and medium- to fine-grained clastic and chemical sedimentary rocks. Most rock types are metamorphosed. The principal structural feature is a ductile shear zone with intra-shear zone boudins of pillow lava and ultramafic rock. Below 400 m, mineralisation forms linear, parallel zones whereas in the upper 300 m there is a much more complex geometry controlled by multiple fault and shear zone orientations. Several styles of quartz veining are present. Mineralisation formed in a single major event post-dating the emplacement of the major rock types. Total measured, indicated and inferred resources at December 1996 were 38 300 000 t grading 2.9 g/t Au., The deposit, in Western Australia, is a recent discovery in an area of thick transported overburden and deep weathering. The main rock types are komatiite flows and intrusions, high-Mg and tholeiitic basalt and dolerite, intermediate to felsic volcanic rocks, internal granitoid plutons and medium- to fine-grained clastic and chemical sedimentary rocks. Most rock types are metamorphosed. The principal structural feature is a ductile shear zone with intra-shear zone boudins of pillow lava and ultramafic rock. Below 400 m, mineralisation forms linear, parallel zones whereas in the upper 300 m there is a much more complex geometry controlled by multiple fault and shear zone orientations. Several styles of quartz veining are present. Mineralisation formed in a single major event post-dating the emplacement of the major rock types. Total measured, indicated and inferred resources at December 1996 were 38 300 000 t grading 2.9 g/t Au.

The deposits, in Western Australia, are in Archaean greenstone rocks of the Pilbara Craton. Metamorphic grade and strain are very low to low, such that primary textures and structures are well preserved in the volcanogenic massive sulphide mineralisation, and in volcanic and sedimentary rocks. Five of the main deposits are associated with faults radiating from the Strelley Granite. Mineralisation is associated with feldspar destructive chlorite-quartz alteration. Sulphide mineralisation is typically zoned downwards from Zn(+/-Pb)-rich to Cu-rich. Indicated and inferred resources at March 1997 were estimated as 2 800 000 t grading 10.7% Zn and 0.6% Cu and 2 500 000 t grading 4% Cu and 1.1% Zn at Sulphur Springs, 1 700 000 t grading 9.8% Zn and 0.6% Cu at Kangaroo Caves and 600 000 t grading 7.8% Zn and 0.3% Cu at Bernts., The deposits, in Western Australia, are in Archaean greenstone rocks of the Pilbara Craton. Metamorphic grade and strain are very low to low, such that primary textures and structures are well preserved in the volcanogenic massive sulphide mineralisation, and in volcanic and sedimentary rocks. Five of the main deposits are associated with faults radiating from the Strelley Granite. Mineralisation is associated with feldspar destructive chlorite-quartz alteration. Sulphide mineralisation is typically zoned downwards from Zn(+/-Pb)-rich to Cu-rich. Indicated and inferred resources at March 1997 were estimated as 2 800 000 t grading 10.7% Zn and 0.6% Cu and 2 500 000 t grading 4% Cu and 1.1% Zn at Sulphur Springs, 1 700 000 t grading 9.8% Zn and 0.6% Cu at Kangaroo Caves and 600 000 t grading 7.8% Zn and 0.3% Cu at Bernts.

The Ni sulphide deposits, in Western Australia, occur in Archaean greenstones, hosted by the Black Swan komatiite. Large areas of this have been subjected to intense carbonation. The Silver Swan massive sulphide deposit is a discrete, steeply plunging long shoot of massive pyrrhotite, pentlandite and pyrite with or without chalcopyrite, magnetite and ferrochromite mineralisation on the footwall contact of the Black Swan komatiite, with an indicated resource of 450 000 t grading 14% Ni. The Cygnet disseminated deposit is a coherent, uniform lens of pyrite-millerite+/-vaesite with a total indicated and inferred resource of 3 400 000 t grading 1.42% Ni. The Black Swan low grade disseminated deposit consists of a central elongate zone of disseminated pyrite-millerite-magnetite-violarite surrounded by several discrete, much smaller mineralised zones. It contains an inferred resource of 7 000 000 t grading 0.8% Ni. Development at Silver Swan began in March 1996; Cygnet may be developed later using the Silver Swan decline. There are no plans to develop Black Swan., The Ni sulphide deposits, in Western Australia, occur in Archaean greenstones, hosted by the Black Swan komatiite. Large areas of this have been subjected to intense carbonation. The Silver Swan massive sulphide deposit is a discrete, steeply plunging long shoot of massive pyrrhotite, pentlandite and pyrite with or without chalcopyrite, magnetite and ferrochromite mineralisation on the footwall contact of the Black Swan komatiite, with an indicated resource of 450 000 t grading 14% Ni. The Cygnet disseminated deposit is a coherent, uniform lens of pyrite-millerite+/-vaesite with a total indicated and inferred resource of 3 400 000 t grading 1.42% Ni. The Black Swan low grade disseminated deposit consists of a central elongate zone of disseminated pyrite-millerite-magnetite-violarite surrounded by several discrete, much smaller mineralised zones. It contains an inferred resource of 7 000 000 t grading 0.8% Ni. Development at Silver Swan began in March 1996; Cygnet may be developed later using the Silver Swan decline. There are no plans to develop Black Swan.

The deposits, in Western Australia, lie in the NE of the Pilbara Craton, where Archaean granitoids are overlain by a dominantly volcanic greenstone sequence. This is unconformably overlain by clastic sediment and banded iron formation, with interbedded mafic volcanic rocks, locally haematitic conglomerates, shales, sandstones and limestones. Dolerite, quartz, pegmatite and granite dykes and veins intrude the Archaean units. Iron ore has been discovered in Archaean stratabound lode deposits, Proterozoic conglomerates, Mesozoic-Tertiary crustal deposits and Tertiary scree. The Y2-3 orebody is a large, continuous stratabound lode containing haematite, with relict banding from original BIF. The Y10 deposit comprises moderately hard, rounded haematitic pebbles cemented by a fine grained haematite-sand matrix. Open cut mining commenced in 1993, with 15 800 000 t being mined from both deposits by May 1996. Total pre-mining measured resources at Y2-3 were 65 000 000 t at 64.7% Fe and at Y10 were 23 600 000 t of ore at 61.2% Fe., The deposits, in Western Australia, lie in the NE of the Pilbara Craton, where Archaean granitoids are overlain by a dominantly volcanic greenstone sequence. This is unconformably overlain by clastic sediment and banded iron formation, with interbedded mafic volcanic rocks, locally haematitic conglomerates, shales, sandstones and limestones. Dolerite, quartz, pegmatite and granite dykes and veins intrude the Archaean units. Iron ore has been discovered in Archaean stratabound lode deposits, Proterozoic conglomerates, Mesozoic-Tertiary crustal deposits and Tertiary scree. The Y2-3 orebody is a large, continuous stratabound lode containing haematite, with relict banding from original BIF. The Y10 deposit comprises moderately hard, rounded haematitic pebbles cemented by a fine grained haematite-sand matrix. Open cut mining commenced in 1993, with 15 800 000 t being mined from both deposits by May 1996. Total pre-mining measured resources at Y2-3 were 65 000 000 t at 64.7% Fe and at Y10 were 23 600 000 t of ore at 61.2% Fe.

The deposit, in Western Australia, lies in the Archaean Lake Johnston greenstone belt, which comprises a folded, homoclinal sequence of felsic to mafic volcanic and sedimentary rocks, including banded iron formation and intrusive ultramafic units. The bedrock is masked by a laterite profile. The orebody is tabular and consists of distinctly different southern and northern zones with unique host lithology. Mineralisation in the southern zone occurs in the thickest portion of the central ultramafic unit and consists of a zone of mainly disseminated sulphides underlain by a narrow basal massive sulphide zone. The northern zone is entirely hosted by felsic volcanics which form the footwall to the central ultramafic unit, and comprises massive sulphide layers and zones of stringer sulphides. The deposit had an inferred and indicated resource at 26 July 1996 of 12 000 000 t at 1.55% Ni., The deposit, in Western Australia, lies in the Archaean Lake Johnston greenstone belt, which comprises a folded, homoclinal sequence of felsic to mafic volcanic and sedimentary rocks, including banded iron formation and intrusive ultramafic units. The bedrock is masked by a laterite profile. The orebody is tabular and consists of distinctly different southern and northern zones with unique host lithology. Mineralisation in the southern zone occurs in the thickest portion of the central ultramafic unit and consists of a zone of mainly disseminated sulphides underlain by a narrow basal massive sulphide zone. The northern zone is entirely hosted by felsic volcanics which form the footwall to the central ultramafic unit, and comprises massive sulphide layers and zones of stringer sulphides. The deposit had an inferred and indicated resource at 26 July 1996 of 12 000 000 t at 1.55% Ni.

The deposit, in Western Australia, lies within the Norseman-Wiluna greenstone belt in the Hampton Boulder fault zone. Differentiated dolerite and felsic sedimentary rocks occur on the western side of the pit and highly altered ultramafic rocks on the east. Mineralisation is centred on a series of broadly concordant felsic porphyry dykes which were intruded along the fault zone into deformed and highly schistose rocks. The mineralised system is subvertical and extends for at least 200 m below the initial pit floor. Gold is associated with silicification and pyrite. The structure within the pit is strongly controlled by the distribution of high strain shear zones and associated splay faults. Mining was carried out between 1984 and 1996 and 10 323 518 t of ore were mined to recover 693 698 oz of gold., The deposit, in Western Australia, lies within the Norseman-Wiluna greenstone belt in the Hampton Boulder fault zone. Differentiated dolerite and felsic sedimentary rocks occur on the western side of the pit and highly altered ultramafic rocks on the east. Mineralisation is centred on a series of broadly concordant felsic porphyry dykes which were intruded along the fault zone into deformed and highly schistose rocks. The mineralised system is subvertical and extends for at least 200 m below the initial pit floor. Gold is associated with silicification and pyrite. The structure within the pit is strongly controlled by the distribution of high strain shear zones and associated splay faults. Mining was carried out between 1984 and 1996 and 10 323 518 t of ore were mined to recover 693 698 oz of gold.

The deposit, in Western Australia, lies within the Norseman-Wiluna greenstone belt, covered by a lateritic weathering profile about 50 m thick. Mineralisation occurs as lenses of quartz-vein reef of variable width and extent with sheared, altered and mineralised selvages. The primary mineralisation was emplaced in dilatant lenses within the Two Boys shear zone. Mining in the Higginsville area commenced in around 1900 and mine development at Two Boys started in January 1997, based on a proved and probable ore reserve estimated to be 230 000 t at 12.29 g/t gold., The deposit, in Western Australia, lies within the Norseman-Wiluna greenstone belt, covered by a lateritic weathering profile about 50 m thick. Mineralisation occurs as lenses of quartz-vein reef of variable width and extent with sheared, altered and mineralised selvages. The primary mineralisation was emplaced in dilatant lenses within the Two Boys shear zone. Mining in the Higginsville area commenced in around 1900 and mine development at Two Boys started in January 1997, based on a proved and probable ore reserve estimated to be 230 000 t at 12.29 g/t gold.

The deposit, in Western Australia, occurs in greenstones near the Ida fault. The host ultramafic and mafic sequence has been folded. The mineralised folded and sheared mafic host is completely contained within the ultramafic body. Gold mineralisation occurs in three adjacent geological settings: in lateritised quartz-sericite mafic schist overlying a large ultramafic body, in the ultramafic rock 10 to 30 m below the mafic rock contact and in a gold-enriched horizon overlying both deposits at 15 to 20 m depth, where gold is dispersed in grit at the base of a palaeochannel cut into the weathered Archaean rocks. Measured, indicated and inferred resources estimated in October 1996 are 2 470 000 t averaging 1.45 g/t gold., The deposit, in Western Australia, occurs in greenstones near the Ida fault. The host ultramafic and mafic sequence has been folded. The mineralised folded and sheared mafic host is completely contained within the ultramafic body. Gold mineralisation occurs in three adjacent geological settings: in lateritised quartz-sericite mafic schist overlying a large ultramafic body, in the ultramafic rock 10 to 30 m below the mafic rock contact and in a gold-enriched horizon overlying both deposits at 15 to 20 m depth, where gold is dispersed in grit at the base of a palaeochannel cut into the weathered Archaean rocks. Measured, indicated and inferred resources estimated in October 1996 are 2 470 000 t averaging 1.45 g/t gold.

The deposit, in Western Australia, is buried beneath shallow alluvium in the Gullewa greenstone belt. It occurs within 5 km of a major primary fault, immediately adjacent to a secondary splay fault, close to a dolerite dyke and an internal granite, and intimately associated with lamprophyric intrusions. The deposit has a high Cu content - West lode averages 2.3% Cu, with local grades over 30%. The Ag content is also unusually high. The deposit probably formed in a low temperature, relatively shallow environment where brittle fracture was more important than shearing. The indicated plus inferred resource is 665 000 t at 4.6 g/t Au and 1.8% Cu., The deposit, in Western Australia, is buried beneath shallow alluvium in the Gullewa greenstone belt. It occurs within 5 km of a major primary fault, immediately adjacent to a secondary splay fault, close to a dolerite dyke and an internal granite, and intimately associated with lamprophyric intrusions. The deposit has a high Cu content - West lode averages 2.3% Cu, with local grades over 30%. The Ag content is also unusually high. The deposit probably formed in a low temperature, relatively shallow environment where brittle fracture was more important than shearing. The indicated plus inferred resource is 665 000 t at 4.6 g/t Au and 1.8% Cu.

The massive and disseminated deposit, in Western Australia, is part of a single, komatiite-hosted nickel sulphide mineralised system occurring in the Archaean Agnew-Wiluna greenstone belt. Massive sulphide mineralisation typically contains 4.0-6.0% Ni and disseminated sulphides contain 0.7-4.0% Ni. Primary sulphides comprise pyrrhotite and pentlandite with trace quantities of chalcopyrite. Hydrothermal alteration introduced As and supergene alteration resulted in mixed assemblages of violarite, bravoite, millerite, pyrite, marcasite and magnetite. Open pit mining began in 1989 and production is currently at a rate of 800 000 t/a, with 3 200 000 t of ore being mined to June 1997. At June 1996, remaining proved and probable reserves were 6 400 000 t at 2.22% Ni., The massive and disseminated deposit, in Western Australia, is part of a single, komatiite-hosted nickel sulphide mineralised system occurring in the Archaean Agnew-Wiluna greenstone belt. Massive sulphide mineralisation typically contains 4.0-6.0% Ni and disseminated sulphides contain 0.7-4.0% Ni. Primary sulphides comprise pyrrhotite and pentlandite with trace quantities of chalcopyrite. Hydrothermal alteration introduced As and supergene alteration resulted in mixed assemblages of violarite, bravoite, millerite, pyrite, marcasite and magnetite. Open pit mining began in 1989 and production is currently at a rate of 800 000 t/a, with 3 200 000 t of ore being mined to June 1997. At June 1996, remaining proved and probable reserves were 6 400 000 t at 2.22% Ni.

The deposit, in Western Australia, was previously called Agnew and occurs in the Agnew-Wiluna greenstone belt. The deposit is the largest single accumulation of Class 1 komatiite-hosted nickel sulphide mineralisation in the world, and is the largest known occurrence in the Yilgarn Craton. Mineralisation occurs in massive and disseminated sulphides hosted by serpentinised ultramafic rock (olivine mesocumulate to adcumulate). The ultramafic rocks were probably deposited during two separate komatiite eruptive episodes separated by a period in which a thick succession of felsic volcaniclastic sediment was deposited. Perseverance is currently being mined underground, with proved and probable reserves to June 1996 totalling 31 300 000 t at 1.65% nickel., The deposit, in Western Australia, was previously called Agnew and occurs in the Agnew-Wiluna greenstone belt. The deposit is the largest single accumulation of Class 1 komatiite-hosted nickel sulphide mineralisation in the world, and is the largest known occurrence in the Yilgarn Craton. Mineralisation occurs in massive and disseminated sulphides hosted by serpentinised ultramafic rock (olivine mesocumulate to adcumulate). The ultramafic rocks were probably deposited during two separate komatiite eruptive episodes separated by a period in which a thick succession of felsic volcaniclastic sediment was deposited. Perseverance is currently being mined underground, with proved and probable reserves to June 1996 totalling 31 300 000 t at 1.65% nickel.

The deposit, in Western Australia, occurs in the Gum Creek greenstone belt. Gold mineralisation is associated with quartz-pyrrhotite veins hosted by banded iron formation. There are two gold-bearing shoots at the Omega pit, one where the BIF changes strike due to an open fold and the other consisting of high-grade quartz veins. Open cut mining of a proved reserve of 190 000 t at 6.56 g/t gold was carried out between April 1991 and December 1992, with 37 600 oz of gold being recovered. Trial underground mining was carried out in 1996 and recent drilling has shown that the mineralisation continues at depth, where an indicated resource of 287 500 t at 7.57 g/t gold has been outlined., The deposit, in Western Australia, occurs in the Gum Creek greenstone belt. Gold mineralisation is associated with quartz-pyrrhotite veins hosted by banded iron formation. There are two gold-bearing shoots at the Omega pit, one where the BIF changes strike due to an open fold and the other consisting of high-grade quartz veins. Open cut mining of a proved reserve of 190 000 t at 6.56 g/t gold was carried out between April 1991 and December 1992, with 37 600 oz of gold being recovered. Trial underground mining was carried out in 1996 and recent drilling has shown that the mineralisation continues at depth, where an indicated resource of 287 500 t at 7.57 g/t gold has been outlined.

The deposits, in Western Australia, lie within an Archaean supracrustal greenstone sequence of volcanic, intrusive and sedimentary rocks. Gold mineralisation occurs in or near structurally deformed BIF along the western limb of the Kurrajong syncline. In fresh mineralised BIF, the gold is associated with quartz-carbonate-pyrite-pyrrhotite stringers which disrupt, fracture and replace well laminated BIF. Other mineralisation is associated with Fe-rich sediments, sheared mafic rocks, narrow quartz porphyry intrusives, granitoids, alluvial wash within a palaeochannel and laterites. Ore was mined from 22 separate open pits from 1988 to 1996, producing 6 420 000 t of ore grading 2.65 g/t gold. At 30 June 1996, total open open pit, underground and stockpile identified resources were 5 650 000 t at 2.1 g/t gold., The deposits, in Western Australia, lie within an Archaean supracrustal greenstone sequence of volcanic, intrusive and sedimentary rocks. Gold mineralisation occurs in or near structurally deformed BIF along the western limb of the Kurrajong syncline. In fresh mineralised BIF, the gold is associated with quartz-carbonate-pyrite-pyrrhotite stringers which disrupt, fracture and replace well laminated BIF. Other mineralisation is associated with Fe-rich sediments, sheared mafic rocks, narrow quartz porphyry intrusives, granitoids, alluvial wash within a palaeochannel and laterites. Ore was mined from 22 separate open pits from 1988 to 1996, producing 6 420 000 t of ore grading 2.65 g/t gold. At 30 June 1996, total open open pit, underground and stockpile identified resources were 5 650 000 t at 2.1 g/t gold.

The deposit, in Western Australia, is hosted by tholeiitic to high-Mg basalt and dolerite that has undergone low grade metamorphism. Mineralisation is structurally controlled by a fault zone which forms part of the brittle-ductile Wiluna fault system. In the high grade ore zones the dominant carbonate species is dolomite, and gold occurs as submicroscopic particles or chemically bound within fine grained pyrite and arsenopyrite. At December 1997, the deposit contained proved and probable reserves of 1 900 000 t at an average grade of 8.5 g/t gold and an additional inferred resource of 600 000 t at 7.3 g/t gold. The deposit is being mined at a rate of 400 000 t/a from a decline which will access the orebody to 600 m below the surface. Due to the extremely refractory nature of the primary mineralisation, an innovative bacterial oxidation plant, based on the BIOX process, is used., The deposit, in Western Australia, is hosted by tholeiitic to high-Mg basalt and dolerite that has undergone low grade metamorphism. Mineralisation is structurally controlled by a fault zone which forms part of the brittle-ductile Wiluna fault system. In the high grade ore zones the dominant carbonate species is dolomite, and gold occurs as submicroscopic particles or chemically bound within fine grained pyrite and arsenopyrite. At December 1997, the deposit contained proved and probable reserves of 1 900 000 t at an average grade of 8.5 g/t gold and an additional inferred resource of 600 000 t at 7.3 g/t gold. The deposit is being mined at a rate of 400 000 t/a from a decline which will access the orebody to 600 m below the surface. Due to the extremely refractory nature of the primary mineralisation, an innovative bacterial oxidation plant, based on the BIOX process, is used.

The deposits, in Western Australia, occur in volcanic and sedimentary rocks within the Lawlers greenstone and Scotty Creek formations. Gold mineralisation is controlled by and contained within prominent structurally prepared zones, contact flexures and allied shears. Rheological contrast played a frequent and critical role in their formation. Mineralisation post-dates formation of the Lawlers Anticline and peak metamorphism. Mineralisation assemblages are either quartz-sulphide depleted as at the Redeemer Main, Cox-Crusader, Claudius Creek, Deliverer and Pilgrim lodes or quartz-sulphide enriched as at the Zone 2, Zone 3 and Emu lodes. Total proved and probable reserves at June 1996 were 7 100 000 t at 4.5 g/t gold with total additional indicated and inferred resources of 7 600 000 t at 4.04 g/t gold., The deposits, in Western Australia, occur in volcanic and sedimentary rocks within the Lawlers greenstone and Scotty Creek formations. Gold mineralisation is controlled by and contained within prominent structurally prepared zones, contact flexures and allied shears. Rheological contrast played a frequent and critical role in their formation. Mineralisation post-dates formation of the Lawlers Anticline and peak metamorphism. Mineralisation assemblages are either quartz-sulphide depleted as at the Redeemer Main, Cox-Crusader, Claudius Creek, Deliverer and Pilgrim lodes or quartz-sulphide enriched as at the Zone 2, Zone 3 and Emu lodes. Total proved and probable reserves at June 1996 were 7 100 000 t at 4.5 g/t gold with total additional indicated and inferred resources of 7 600 000 t at 4.04 g/t gold.

The Norseman goldfield, Western Australia, was discovered in 1894 and recent mining has been carried out at Bullen, OK, Scotia and Harlequin. The most common gold mineralisation style consists of quartz veins hosted within sheared and metamorphosed Archaean mafic rocks, but each of the orebodies differs to some extent from the veins which have been the big producers in the past. Since 1984, total contained gold production from the mines has been 129 286 oz from OK, 155 040 oz from Scotia, 119 529 oz from Bullen and 76 572 oz from Harlequin. Total proved and probable reserves for the area at June 1996 were 958 000 t of ore grading 13.6 g/t gold., The Norseman goldfield, Western Australia, was discovered in 1894 and recent mining has been carried out at Bullen, OK, Scotia and Harlequin. The most common gold mineralisation style consists of quartz veins hosted within sheared and metamorphosed Archaean mafic rocks, but each of the orebodies differs to some extent from the veins which have been the big producers in the past. Since 1984, total contained gold production from the mines has been 129 286 oz from OK, 155 040 oz from Scotia, 119 529 oz from Bullen and 76 572 oz from Harlequin. Total proved and probable reserves for the area at June 1996 were 958 000 t of ore grading 13.6 g/t gold.

The deposit, in Western Australia, lies in the Archaean Yilgarn Craton along the Yilgarn Star shear zone, which is bound to the stratigraphic contact of a thick unit of altered metagreywacke with ultramafic amphibole-chlorite rocks. Gold is associated with structurally controlled dilatant sites within the veined, ductile-brittle shear zone. The level of mineralisation is closely linked to the intensity of shearing and concentration of veining. All economic resources occur within 50 m of the metasediment-ultramafic rock contact zone. Mining began in November 1991 and to December 1996, 466 911 fine oz gold were produced from 3 360 000 t of ore. Reserves are 1 590 000 t at 3.68 g/t gold., The deposit, in Western Australia, lies in the Archaean Yilgarn Craton along the Yilgarn Star shear zone, which is bound to the stratigraphic contact of a thick unit of altered metagreywacke with ultramafic amphibole-chlorite rocks. Gold is associated with structurally controlled dilatant sites within the veined, ductile-brittle shear zone. The level of mineralisation is closely linked to the intensity of shearing and concentration of veining. All economic resources occur within 50 m of the metasediment-ultramafic rock contact zone. Mining began in November 1991 and to December 1996, 466 911 fine oz gold were produced from 3 360 000 t of ore. Reserves are 1 590 000 t at 3.68 g/t gold.

The region, in Western Australia, forms part of the Norseman-Wiluna greenstone belt. Since 1988, deposits have been found in nearly all the stratigraphic units present: basalts, komatiites, slates, dolerite and intermediate and felsic intrusive rocks. Basalt-hosted deposits are Sirius, Britannia, Santa Ana and Bahama, the Repulse footwall lode occurs within slates, dolerite-hosted orebodies are Argo, Apollo and Cave Rocks, and the Intrepide and Redoutable deposits occur in komatiite-felsic intrusive rocks. A common feature of many of the deposits is a NNW-trending structure associated with rocks of contrasting competency. Such an environment allows passage of ore fluids in either dilatant, compressive or transpressive regimes. Total reserves and resources at June 1997 were 67 200 000 t at 3.33 g/t gold., The region, in Western Australia, forms part of the Norseman-Wiluna greenstone belt. Since 1988, deposits have been found in nearly all the stratigraphic units present: basalts, komatiites, slates, dolerite and intermediate and felsic intrusive rocks. Basalt-hosted deposits are Sirius, Britannia, Santa Ana and Bahama, the Repulse footwall lode occurs within slates, dolerite-hosted orebodies are Argo, Apollo and Cave Rocks, and the Intrepide and Redoutable deposits occur in komatiite-felsic intrusive rocks. A common feature of many of the deposits is a NNW-trending structure associated with rocks of contrasting competency. Such an environment allows passage of ore fluids in either dilatant, compressive or transpressive regimes. Total reserves and resources at June 1997 were 67 200 000 t at 3.33 g/t gold.

The deposit, in Western Australia, is hosted by felsic volcaniclastic sedimentary and pyroclastic rocks intruded by feldspar porphyry. A thin continuous unit of graphitic black shale occurs on the eastern side. In the Western contact mineralisation zone, mineralisation is related to shallowly SW-dipping quartz veins with associated bleaching, silicification and pyrite alteration. Eastern contact mineralisation occurs within a small juxtaposed flat-lying lens of fine-grained sediment within felsic rocks along a well defined volcanic-black shale contact above a porphyry intrusion. All rock types have been extensively weathered, with the base of oxidation ranging from about 40 m in porphyry to 60 m in volcaniclastic rocks. Modern open pit production from Binduli began in 1993 and 1 815 087 t of ore grading 2.3 g/t gold has been mined; total resources are 19 300 000 t at 1.4 g/t Au. Resources at Centurion comprise 2 600 000 t of ore at 1.9 g/t gold., The deposit, in Western Australia, is hosted by felsic volcaniclastic sedimentary and pyroclastic rocks intruded by feldspar porphyry. A thin continuous unit of graphitic black shale occurs on the eastern side. In the Western contact mineralisation zone, mineralisation is related to shallowly SW-dipping quartz veins with associated bleaching, silicification and pyrite alteration. Eastern contact mineralisation occurs within a small juxtaposed flat-lying lens of fine-grained sediment within felsic rocks along a well defined volcanic-black shale contact above a porphyry intrusion. All rock types have been extensively weathered, with the base of oxidation ranging from about 40 m in porphyry to 60 m in volcaniclastic rocks. Modern open pit production from Binduli began in 1993 and 1 815 087 t of ore grading 2.3 g/t gold has been mined; total resources are 19 300 000 t at 1.4 g/t Au. Resources at Centurion comprise 2 600 000 t of ore at 1.9 g/t gold.

The deposit, in Western Australia, is concealed by 40 m of gold-depleted cover and lies within a greenstone succession ranging from a basal basalt through chert and ultramafic rocks into upper felsic volcanic rocks and sediments. Open pit mining began in November 1992 and deeper resource blocks are being defined for underground working. Around 70% of the total resource is contained within the Kanowna Belle porphyry. Gold distribution and wall rock alteration are directly related to the Fitzroy shear zone and oblique structures developed in the hanging wall of this shear. Ore mined to the end of June 1996 was 4 300 000 t at 3.86 g/t Au, and remaining open pit proved and probable reserves were 4 500 000 t at 4.9 g/t Au. Underground proved and probable reserves for the first mining block beneath the open pit were 2 900 000 t at 7.0 g/t Au., The deposit, in Western Australia, is concealed by 40 m of gold-depleted cover and lies within a greenstone succession ranging from a basal basalt through chert and ultramafic rocks into upper felsic volcanic rocks and sediments. Open pit mining began in November 1992 and deeper resource blocks are being defined for underground working. Around 70% of the total resource is contained within the Kanowna Belle porphyry. Gold distribution and wall rock alteration are directly related to the Fitzroy shear zone and oblique structures developed in the hanging wall of this shear. Ore mined to the end of June 1996 was 4 300 000 t at 3.86 g/t Au, and remaining open pit proved and probable reserves were 4 500 000 t at 4.9 g/t Au. Underground proved and probable reserves for the first mining block beneath the open pit were 2 900 000 t at 7.0 g/t Au.

The deposit, in Western Australia, occurs in the Archaean Norseman-Wiluna greenstone belt in an ultramafic sequence overlain by basalt and topped by andesite and sediment. Mineralisation is stratabound and occurs as a series of subhorizontal layers entirely overlying the dunite. Higher grade zones are commonly associated with shear and crosscutting structures or dykes which have enhanced the weathering process. The total identified mineral resource is 217 000 000 t at 0.7% Ni and 0.04% Co. Proved and probable reserves for the Bunyip Dam and Central pits portion of the deposit are 24 600 000 t at 1.0% Ni and 0.08% Co., The deposit, in Western Australia, occurs in the Archaean Norseman-Wiluna greenstone belt in an ultramafic sequence overlain by basalt and topped by andesite and sediment. Mineralisation is stratabound and occurs as a series of subhorizontal layers entirely overlying the dunite. Higher grade zones are commonly associated with shear and crosscutting structures or dykes which have enhanced the weathering process. The total identified mineral resource is 217 000 000 t at 0.7% Ni and 0.04% Co. Proved and probable reserves for the Bunyip Dam and Central pits portion of the deposit are 24 600 000 t at 1.0% Ni and 0.08% Co.

The nine deposits, in Western Australia, are hosted by a laterite profile developed on Archaean serpentinised olivine cumulates within a sequence dominated by immature feldspathic, clastic and volcaniclastic sediment. Metamorphism is characterised by assemblages from prehnite-pumpellyite through greenschist to upper amphibolite facies. Ni-Co mineralisation is hosted mainly in smectite, saprolite and ferruginous saprolite zones, with lesser amounts within ferruginous and ferruginous smectite zones. Significant concentrations of Ni are contained in smectite clays with lesser amounts in Mn oxides, serpentine and chlorite. Most of the Co is associated with Mn oxide minerals. At May 1996, resources were 125 200 000 t at 1.02% Ni and 0.065% Co, 66 400 000 t being measured resources and 58 800 000 indicated. Production in the area is scheduled by the beginning of 1998., The nine deposits, in Western Australia, are hosted by a laterite profile developed on Archaean serpentinised olivine cumulates within a sequence dominated by immature feldspathic, clastic and volcaniclastic sediment. Metamorphism is characterised by assemblages from prehnite-pumpellyite through greenschist to upper amphibolite facies. Ni-Co mineralisation is hosted mainly in smectite, saprolite and ferruginous saprolite zones, with lesser amounts within ferruginous and ferruginous smectite zones. Significant concentrations of Ni are contained in smectite clays with lesser amounts in Mn oxides, serpentine and chlorite. Most of the Co is associated with Mn oxide minerals. At May 1996, resources were 125 200 000 t at 1.02% Ni and 0.065% Co, 66 400 000 t being measured resources and 58 800 000 indicated. Production in the area is scheduled by the beginning of 1998.

The deposits, in Western Australia, lie in the Archaean Forrestania greenstone belt, which comprises a lowermost sequence of tholeiitic basalt and numerous thin banded iron formation and chert units. This is overlain by psammitic to pelitic schists. All the nickel sulphide deposits of the belt occur within the Eastern and Western ultramafic belts. The Cosmic Boy deposit is the largest deposit, containing around 4 000 000 t at 2.4% Ni. Primary mineralisation consists of a strong dissemination of pyrrhotite-pentlandite+/-pyrite and chalcopyrite, with Ni grades between 0.7 and 5%. The Flying Fox deposit is a high grade massive sulphide deposit which has been mined since 1992. Total production is expected to be about 200 000 t at 3.1% Ni. At January 1997 the proved and probable ore reserves for the Forrestania area were 1 100 000 t at 1.9% Ni., The deposits, in Western Australia, lie in the Archaean Forrestania greenstone belt, which comprises a lowermost sequence of tholeiitic basalt and numerous thin banded iron formation and chert units. This is overlain by psammitic to pelitic schists. All the nickel sulphide deposits of the belt occur within the Eastern and Western ultramafic belts. The Cosmic Boy deposit is the largest deposit, containing around 4 000 000 t at 2.4% Ni. Primary mineralisation consists of a strong dissemination of pyrrhotite-pentlandite+/-pyrite and chalcopyrite, with Ni grades between 0.7 and 5%. The Flying Fox deposit is a high grade massive sulphide deposit which has been mined since 1992. Total production is expected to be about 200 000 t at 3.1% Ni. At January 1997 the proved and probable ore reserves for the Forrestania area were 1 100 000 t at 1.9% Ni.

The deposit, in Western Australia, lies within the low-grade metamorphic Lake Violet greenstone belt in the Yilgarn Craton, with the main rock type in the area being pillowed and tholeiitic basalt and dolerite. Mineralogy includes relict primary minerals and those attributable to low grade regional metamorphism and subsequent hydrothermal alteration. Gold mineralisation is hosted by fault breccias, hydrobreccias in dilation zones, fracture-fill veins and shear zones enveloped by zoned alteration haloes which overprint the regional metamorphism. Mineralisation was a late stage tectonic and alteration event and often followed earlier open, colloform structures as crack-seal vein structures. Mining is by open cast methods in several pits, with production to the end of March 1997 being 150 454 oz of gold from 967 200 t of ore at a head grade of 5.33 g/t. The remaining indicated and measured resource is 6 593 000 t at 4.71 g/t Au., The deposit, in Western Australia, lies within the low-grade metamorphic Lake Violet greenstone belt in the Yilgarn Craton, with the main rock type in the area being pillowed and tholeiitic basalt and dolerite. Mineralogy includes relict primary minerals and those attributable to low grade regional metamorphism and subsequent hydrothermal alteration. Gold mineralisation is hosted by fault breccias, hydrobreccias in dilation zones, fracture-fill veins and shear zones enveloped by zoned alteration haloes which overprint the regional metamorphism. Mineralisation was a late stage tectonic and alteration event and often followed earlier open, colloform structures as crack-seal vein structures. Mining is by open cast methods in several pits, with production to the end of March 1997 being 150 454 oz of gold from 967 200 t of ore at a head grade of 5.33 g/t. The remaining indicated and measured resource is 6 593 000 t at 4.71 g/t Au.

The area, in Western Australia, occurs within the Yandal greenstone belt and consists of the Lotus, Cockburn, Success, Parmelia, Challenger and Dragon deposits. The Archaean volcanic-sedimentary succession is separated from felsic and mafic gneiss on the western side by the Mount McClure fault and a second major shear zone links this fault with the Ninnis fault. Gold ores within the Lotus dolerite have up to 10% pyrite as blebs and veinlets in quartz veins and altered dolerite. Mineralisation at Cockburn is associated with a stockwork of irregular quartz-carbonate+/-chlorite veins. The other four are geologically similar with mineralisation generally associated with quartz veins subparallel to foliation. At June 1996, total proved and probable reserves for the Mount McClure project were 12 566 000 t of ore grading 2.0 g/t gold. Current mine production comprises oxide ore from the Cockburn and Lotus North open pits and primary ore from the Lotus Deeps underground mine., The area, in Western Australia, occurs within the Yandal greenstone belt and consists of the Lotus, Cockburn, Success, Parmelia, Challenger and Dragon deposits. The Archaean volcanic-sedimentary succession is separated from felsic and mafic gneiss on the western side by the Mount McClure fault and a second major shear zone links this fault with the Ninnis fault. Gold ores within the Lotus dolerite have up to 10% pyrite as blebs and veinlets in quartz veins and altered dolerite. Mineralisation at Cockburn is associated with a stockwork of irregular quartz-carbonate+/-chlorite veins. The other four are geologically similar with mineralisation generally associated with quartz veins subparallel to foliation. At June 1996, total proved and probable reserves for the Mount McClure project were 12 566 000 t of ore grading 2.0 g/t gold. Current mine production comprises oxide ore from the Cockburn and Lotus North open pits and primary ore from the Lotus Deeps underground mine.

The deposits, in Western Australia, lie in the Agnew-Wiluna greenstone belt in a sequence of mafic to ultramafic volcanic rocks and associated interflow sediments. The dominant structure in the area is the Waroonga shear zone. Gold mineralisation in the orebodies is closely associated with quartz veining within medium- to coarse-grained sandstone units. Mineralisation occurred after peak metamorphism and was related to reactivation of D1 faults and the subsequent creation of S3 structures. From 1898 to 1996, 157 823 oz of gold were recovered from the deposits. Resources at 31 December 1996 were 668 000 t of ore at 2.6 g/t gold for Genesis, 832 000 t at 4.5 g/t gold for New Holland and 512 000 t at 9.2 g/t gold for the New Holland South underground deposit., The deposits, in Western Australia, lie in the Agnew-Wiluna greenstone belt in a sequence of mafic to ultramafic volcanic rocks and associated interflow sediments. The dominant structure in the area is the Waroonga shear zone. Gold mineralisation in the orebodies is closely associated with quartz veining within medium- to coarse-grained sandstone units. Mineralisation occurred after peak metamorphism and was related to reactivation of D1 faults and the subsequent creation of S3 structures. From 1898 to 1996, 157 823 oz of gold were recovered from the deposits. Resources at 31 December 1996 were 668 000 t of ore at 2.6 g/t gold for Genesis, 832 000 t at 4.5 g/t gold for New Holland and 512 000 t at 9.2 g/t gold for the New Holland South underground deposit.

The Bluebird goldfield, in Western Australia, contains the Bluebird deposit and the new discoveries of South Junction and Bluebird East. Total proved and probable reserves are 3 035 000 t grading around 2.7 g/t Au. Contact metasomatic gold is present, with mineralisation occurring at the contact between granitoid or felsic porphyry and altered ultramafic rocks. Mineralisation is closely associated with shear structures. The Nannine goldfield consists of the Baileys Island deposits and has total reserves of 58 000 t grading 3.10 g/t Au. The deposits occur in BIF units and in interlayered mafic volcanic rock and BIF near the contact with the overlying formation. The Cuddingwarra field contains the Black Swan and Rapier deposits, with total reserves of 4 551 000 t grading 2.3 g/t Au. Deposits are hosted by quartz and feldspar porphyry intruded into tholeiitic basalts. Gold occurs in quartz veins cutting the porphyry and in laterites., The Bluebird goldfield, in Western Australia, contains the Bluebird deposit and the new discoveries of South Junction and Bluebird East. Total proved and probable reserves are 3 035 000 t grading around 2.7 g/t Au. Contact metasomatic gold is present, with mineralisation occurring at the contact between granitoid or felsic porphyry and altered ultramafic rocks. Mineralisation is closely associated with shear structures. The Nannine goldfield consists of the Baileys Island deposits and has total reserves of 58 000 t grading 3.10 g/t Au. The deposits occur in BIF units and in interlayered mafic volcanic rock and BIF near the contact with the overlying formation. The Cuddingwarra field contains the Black Swan and Rapier deposits, with total reserves of 4 551 000 t grading 2.3 g/t Au. Deposits are hosted by quartz and feldspar porphyry intruded into tholeiitic basalts. Gold occurs in quartz veins cutting the porphyry and in laterites.

The deposit, in Western Australia, is atypical compared with most gold deposits in the Yilgarn Block in that mineralisation is developed in the Archaean sequence and in the overlying transported cover, and is controlled by a gently-dipping thrust duplex system. Gold mineralisation occurs intermittently along a 4.5 km long NE-trending corridor, coincident with a strongly magnetic banded iron formation sequence. There are three styles of primary mineralisation: pyrite replacement of BIF, shear mineralisation and thin quartz-carbonate vein mineralisation. Supergene gold distribution in the transported overburden was probably related to local physical transport of mineralised material during channel infill. Identified mineral resources (including reserves) in July 1996 were 5 970 000 t at 2.6 g/t Au for Sunrise and 11 500 000 t at 3.6 g/t Au for Cleo. The total contained gold for the Sunrise-Cleo deposit exceeds 1 800 000 oz., The deposit, in Western Australia, is atypical compared with most gold deposits in the Yilgarn Block in that mineralisation is developed in the Archaean sequence and in the overlying transported cover, and is controlled by a gently-dipping thrust duplex system. Gold mineralisation occurs intermittently along a 4.5 km long NE-trending corridor, coincident with a strongly magnetic banded iron formation sequence. There are three styles of primary mineralisation: pyrite replacement of BIF, shear mineralisation and thin quartz-carbonate vein mineralisation. Supergene gold distribution in the transported overburden was probably related to local physical transport of mineralised material during channel infill. Identified mineral resources (including reserves) in July 1996 were 5 970 000 t at 2.6 g/t Au for Sunrise and 11 500 000 t at 3.6 g/t Au for Cleo. The total contained gold for the Sunrise-Cleo deposit exceeds 1 800 000 oz.

The Plutonic deposit, Western Australia, was discovered in 1988. Mineralisation is hosted by low-K tholeiitic metabasalt, ultramafic rocks and minor siliceous, graphitic and sulphidic metasediments. The most common form of mineralisation is a series of discrete, subparallel multiple lodes between 1 and 10 m thick. An auriferous laterite deposit occurs on the southern flank of the deposit. Gold is present mainly as native Au disseminated throughout the groundmass or within the silicate gangue. Open cut and underground mining is in progress, with 1 000 000 oz of Au having been produced to January 1996. Production during 1996 was 183 700 oz Au from 2 020 000 t at a grade of 3.6 g/t Au. Total resources at 31 December 1996 were 35 000 000 t containing 7 300 000 oz Au., The Plutonic deposit, Western Australia, was discovered in 1988. Mineralisation is hosted by low-K tholeiitic metabasalt, ultramafic rocks and minor siliceous, graphitic and sulphidic metasediments. The most common form of mineralisation is a series of discrete, subparallel multiple lodes between 1 and 10 m thick. An auriferous laterite deposit occurs on the southern flank of the deposit. Gold is present mainly as native Au disseminated throughout the groundmass or within the silicate gangue. Open cut and underground mining is in progress, with 1 000 000 oz of Au having been produced to January 1996. Production during 1996 was 183 700 oz Au from 2 020 000 t at a grade of 3.6 g/t Au. Total resources at 31 December 1996 were 35 000 000 t containing 7 300 000 oz Au.

The deposit, in Western Australia, is located in a narrow belt of Archaean greenstones between two extensive granite or granite gneiss domains. Mineralisation occurs in a shallowly dipping biotite-rich schist zone within a sequence of sheared mafic amphibolites. The mineralised shear zone is up to 30 m thick and contains a higher grade zone of alteration towards the base of the schist. Mineralisation was possibly initiated along a porphyry-amphibolite contact, with progressive deformation and introduction of fluid leading to pervasive alteration of the shear zone, the intrusion of further porphyry dykes, and gold mineralisation. Mining was carried out between 1906 and 1913 and two further phases of open pit mining (1988-89 and 1993-94) produced 1 650 000 t of ore at 2.79 g/t Au. Decline access for underground mining has provided an additional indicated and inferred resource of 2 810 000 t at 4-5 g/t Au., The deposit, in Western Australia, is located in a narrow belt of Archaean greenstones between two extensive granite or granite gneiss domains. Mineralisation occurs in a shallowly dipping biotite-rich schist zone within a sequence of sheared mafic amphibolites. The mineralised shear zone is up to 30 m thick and contains a higher grade zone of alteration towards the base of the schist. Mineralisation was possibly initiated along a porphyry-amphibolite contact, with progressive deformation and introduction of fluid leading to pervasive alteration of the shear zone, the intrusion of further porphyry dykes, and gold mineralisation. Mining was carried out between 1906 and 1913 and two further phases of open pit mining (1988-89 and 1993-94) produced 1 650 000 t of ore at 2.79 g/t Au. Decline access for underground mining has provided an additional indicated and inferred resource of 2 810 000 t at 4-5 g/t Au.

The deposit, in Western Australia, lies within the Norseman-Wiluna greenstone belt, beneath the site of the historic King of The Hills workings. Vein gold mineralisation is largely shear-hosted, occurring along a shallowly dipping to subvertical granite-greenstone boundary overlying the Tarmoola granodiorite. Irregular and diffuse zones of low grade mineralisation also occur. It is thought that the Tarmoola granodiorite was intruded near the top of the subsurface extension of the shear zone system. Mineralisation is related to strain perturbations along the pluton roof and around its northern edge. Subsequent mineralisation occurs in the form of relatively late, steeply dipping D2 faults and veins adjacent to the granodiorite. In October 1996, proved and probable reserves were 12 973 000 t at 2.6 g/t Au. The deposit is currently being mined by open cast methods., The deposit, in Western Australia, lies within the Norseman-Wiluna greenstone belt, beneath the site of the historic King of The Hills workings. Vein gold mineralisation is largely shear-hosted, occurring along a shallowly dipping to subvertical granite-greenstone boundary overlying the Tarmoola granodiorite. Irregular and diffuse zones of low grade mineralisation also occur. It is thought that the Tarmoola granodiorite was intruded near the top of the subsurface extension of the shear zone system. Mineralisation is related to strain perturbations along the pluton roof and around its northern edge. Subsequent mineralisation occurs in the form of relatively late, steeply dipping D2 faults and veins adjacent to the granodiorite. In October 1996, proved and probable reserves were 12 973 000 t at 2.6 g/t Au. The deposit is currently being mined by open cast methods.

The deposit, in Western Australia, lies within the Archaean Norseman-Wiluna greenstone belt hosted by komatiites, basalts, slates, dolerites and felsic-intermediate porphyries. Mineralised structures were mainly developed on the eastern limb of the NNW-trending Delta Island anticline. The area is bounded to the east by the steeply east-dipping Playa shear zone. Gold mineralisation is associated with foliated and altered host rocks and with accompanying quartz vein systems. Open pit mining began in 1991 with underground development the following year. Production to December 1996 was 2 370 000 t at 4.64 g/t gold. Further proved and probable reserves are 833 000 t at 4.5 g/t gold., The deposit, in Western Australia, lies within the Archaean Norseman-Wiluna greenstone belt hosted by komatiites, basalts, slates, dolerites and felsic-intermediate porphyries. Mineralised structures were mainly developed on the eastern limb of the NNW-trending Delta Island anticline. The area is bounded to the east by the steeply east-dipping Playa shear zone. Gold mineralisation is associated with foliated and altered host rocks and with accompanying quartz vein systems. Open pit mining began in 1991 with underground development the following year. Production to December 1996 was 2 370 000 t at 4.64 g/t gold. Further proved and probable reserves are 833 000 t at 4.5 g/t gold.

The deposit, in Western Australia, is a large tonnage, low grade disseminated nickel sulphide deposit hosted by very large, layered bodies of olivine cumulates within an extrusive komatiite in the Agnew-Wiluna greenstone belt. Mineralisation is almost entirely hosted by a central olivine adcumulate-mesocumulate with primary nickel-bearing sulphides occurring in lobate aggregates in the interstices between former olivine grains. Pentlandite is the most common mineral and is associated with pyrrhotite and magnetite. Three mineralogically defined zones are also present in the weathering profile above the primary ore zone. Mining began in October 1994 and to the end of February 1997 total production was 73 682 t of nickel in concentrate. As of June 1996 measured, indicated and inferred resources were 459 000 000 t at 0.6% nickel., The deposit, in Western Australia, is a large tonnage, low grade disseminated nickel sulphide deposit hosted by very large, layered bodies of olivine cumulates within an extrusive komatiite in the Agnew-Wiluna greenstone belt. Mineralisation is almost entirely hosted by a central olivine adcumulate-mesocumulate with primary nickel-bearing sulphides occurring in lobate aggregates in the interstices between former olivine grains. Pentlandite is the most common mineral and is associated with pyrrhotite and magnetite. Three mineralogically defined zones are also present in the weathering profile above the primary ore zone. Mining began in October 1994 and to the end of February 1997 total production was 73 682 t of nickel in concentrate. As of June 1996 measured, indicated and inferred resources were 459 000 000 t at 0.6% nickel.

The sulphide deposits, in Western Australia, occur in Norseman-Wiluna greenstones associated with komatiite. The volcanic and sedimentary sequence is intruded by granitoid, metamorphosed to amphibolite facies and faulted and folded during four episodes of deformation. Recently discovered deposits in the area have important geological characteristics which differ significantly from the typical Kambalda-style deposit. These deposits are Helmut, Mariners, Blair, Coronet and Carnilya Hill. The area is the largest Ni producer in Australia, producing 40 000 t of Ni in concentrate in the year ending July 1996. As of July 1996, proved and probable reserves were 10 500 000 t at 3.1% Ni., The sulphide deposits, in Western Australia, occur in Norseman-Wiluna greenstones associated with komatiite. The volcanic and sedimentary sequence is intruded by granitoid, metamorphosed to amphibolite facies and faulted and folded during four episodes of deformation. Recently discovered deposits in the area have important geological characteristics which differ significantly from the typical Kambalda-style deposit. These deposits are Helmut, Mariners, Blair, Coronet and Carnilya Hill. The area is the largest Ni producer in Australia, producing 40 000 t of Ni in concentrate in the year ending July 1996. As of July 1996, proved and probable reserves were 10 500 000 t at 3.1% Ni.

The deposit, in Western Australia, occurs in one of several Proterozoic basins between the Pilbara and Yilgarn cratons. An Archaean granite and greenstone basement is unconformably overlain by quartz sandstones, siltstones, extensively silicified stromatolitic dolomite and black carbonaceous shale. Dolerite sills intrude in the north of the deposit. Mineralisation is hosted by carbonate and sandstone horizons and occurs as a subhorizontal sheet. Lead minerals are cerussite, anglesite, pyromorphite and coronadite. The deposit formed from a primary carbonate-hosted Mississippi Valley-type sulphide deposit that was oxidised and upgraded by intense Tertiary weathering. At a 0.1% lead cutoff, the deposit has an inferred resource of 210 000 t at 1.8% lead., The deposit, in Western Australia, occurs in one of several Proterozoic basins between the Pilbara and Yilgarn cratons. An Archaean granite and greenstone basement is unconformably overlain by quartz sandstones, siltstones, extensively silicified stromatolitic dolomite and black carbonaceous shale. Dolerite sills intrude in the north of the deposit. Mineralisation is hosted by carbonate and sandstone horizons and occurs as a subhorizontal sheet. Lead minerals are cerussite, anglesite, pyromorphite and coronadite. The deposit formed from a primary carbonate-hosted Mississippi Valley-type sulphide deposit that was oxidised and upgraded by intense Tertiary weathering. At a 0.1% lead cutoff, the deposit has an inferred resource of 210 000 t at 1.8% lead.

Mineralisation at the deposit, in Western Australia, is hosted by a highly fissile, banded sericite-carbonate schist immediately adjacent to the NW-trending Kingfisher fault. Primary gold mineralisation is aligned parallel to the fault and is directly related to quartz veining. The most significant veins occur at the hanging wall contact and are 0.3 to 4 m wide. A stockwork zone, up to 15 m wide, of quartz-ankerite veins extends into the footwall. It is thought that epigenetic emplacement of gold in the primary zone occurred after regional faulting and during, or immediately after, crosscutting dextral faulting. Mineralising fluids of probable metamorphic origin intruded during deformation. Mining was carried out between August 1990 and June 1996, with recoveries of 264 950 oz of gold from 2 010 000 t of ore from the open pit at a recovered grade of 4.1 g/t and 27 200 oz of gold from 60 000 t of underground ore at a recovered grade of 14.1 g/t., Mineralisation at the deposit, in Western Australia, is hosted by a highly fissile, banded sericite-carbonate schist immediately adjacent to the NW-trending Kingfisher fault. Primary gold mineralisation is aligned parallel to the fault and is directly related to quartz veining. The most significant veins occur at the hanging wall contact and are 0.3 to 4 m wide. A stockwork zone, up to 15 m wide, of quartz-ankerite veins extends into the footwall. It is thought that epigenetic emplacement of gold in the primary zone occurred after regional faulting and during, or immediately after, crosscutting dextral faulting. Mineralising fluids of probable metamorphic origin intruded during deformation. Mining was carried out between August 1990 and June 1996, with recoveries of 264 950 oz of gold from 2 010 000 t of ore from the open pit at a recovered grade of 4.1 g/t and 27 200 oz of gold from 60 000 t of underground ore at a recovered grade of 14.1 g/t.

The deposit occurs close to the Nimary deposits in a greenstone belt in the Yilgarn Craton of Western Australia. It was discovered by surface geochemical sampling, rotary air blast drilling and extensive follow-up drilling. The predominant host rocks are mafic and include tholeiitic basalt, dolerite and spatially associated feldspar-rich porphyritic dykes. Mineralisation comprises quartz-calcite-pyrite veinlets with associated chlorite-carbonate-pyrite-muscovite alteration in a brittle deformation environment. The strong structural control of veinlets and mineralisation in the weathered zone exposed in the open pits indicates that Jundee is a weathered primary gold deposit. Total measured, indicated and inferred resources remaining are 36 000 000 t at 2.4 g/t Au. Production to December 1996 totalled 6.8 t of Au., The deposit occurs close to the Nimary deposits in a greenstone belt in the Yilgarn Craton of Western Australia. It was discovered by surface geochemical sampling, rotary air blast drilling and extensive follow-up drilling. The predominant host rocks are mafic and include tholeiitic basalt, dolerite and spatially associated feldspar-rich porphyritic dykes. Mineralisation comprises quartz-calcite-pyrite veinlets with associated chlorite-carbonate-pyrite-muscovite alteration in a brittle deformation environment. The strong structural control of veinlets and mineralisation in the weathered zone exposed in the open pits indicates that Jundee is a weathered primary gold deposit. Total measured, indicated and inferred resources remaining are 36 000 000 t at 2.4 g/t Au. Production to December 1996 totalled 6.8 t of Au.