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Namakwa Sands is a mining company operating on the west coast of South Africa, producing zircon, rutile and ilmenite. Heavy mineral sands are extracted by wet gravity, magnetic and electrostatic separation. In order to maintain their zircon product specifications, particularly with respect to radioactivity, the reject stream may still contain significant grades of zircon but is associated with penalty elements such as titanium dioxide (TiO2), uranium (U) and thorium (Th). The radioactive components U and Th are associated with the mineral monazite and cause issues in handling and disposal of the material.If monazite could be removed from the reject stream, the remaining material could potentially be sold as a low-grade zircon product. Furthermore, monazite is a valuable mineral in itself due to its content of rare earth elements such as cerium and lanthanum, which are valued in the nuclear and wind-power industries. The separation of monazite from the zircon reject stream is therefore desirable to Namakwa Sands from both an economic and an environmental perspective, by reducing the amount of waste and increasing revenue. Flotation of heavy minerals is rarely practiced due to the effectiveness of gravity and electrostatic separation of coarse particles. However, the physical separation at Namakwa Sands is challenged by fine particle sizes and surface coating issues affecting the surface properties and thus the separation. Froth flotation, which operates within finer particle sizes, is a possible separation method that in combination with surface attrition could selectively separate monazite.The objective of this project is to investigate the use of reverse froth flotation to separate monazite from the final zircon reject stream to obtain a higher-grade zircon product that meets product specifications. The accompanying investigation of the mineralogy and surface coatings of the material will also be critical in understanding the effect of the flotation factors on the success of monazite flotation. This project is broadly divided into two phases of flotation experiments with an accompanying mineralogical investigation of the flotation products. In the first phase of the project, the aim was to find flotation conditions where monazite could selectively be removed from the pulp, i.e. by using reverse flotation. A statistical screening design in the statistical software MODDE (©Umetrics) was used to find the significant parameters and the optimum flotation settings. The investigated parameters were pH, collector type, collector dosage, depressant type, depressant dosage and ultrasonication. The most common monazite collectors in flotation were reported to be oleates, hydroxamates and amine based collectors. More specifically, oleate and hydroxamate collectors have been used for the separation of monazite and zircon, and were therefore the collectors that were used in the first phase.In the second phase of the project, fewer parameters, and narrower intervals were used. More intense mechanical attritioning was also applied in this phase using a custom-built mini pin mill. In two full factorial designs, collector dosage, depressant dosage, pH and attrition intensity were studied.The hydroxamate collector was found not to be selective for any of the minerals, but the oleate collector could selectively recover monazite at a pH of 10 and a collector dosage of 180 g/ton. Further investigation showed that an oleate collector dosage of 315 g/ton resulted in a monazite recovery of 55.6%. The best monazite grade was 71.7% with the oleate collector at a dosage of 215 g/ton and a pH of 10, however the recovery was low with 28.4%. Results showed that selectivity was highly dependent on pH. At a pH value of 9, no selectivity was obtained, and more than 50 % of the pulp was recovered to the concentrate in three minutes. An increase of pH to 11 resulted in only foam recovery. Monazite selectivity was obtained between these two extremes, at a pH of 10. The flotation system was extremely pH-sensitive, which indicates that the point of zero charge for the Namakwa Sands zircon and monazite may lie within this narrow pH interval.The accompanying mineralogical study showed that the final zircon reject composed of mainly zircon, between 70% and 83%. The rutile content was around 7% and the monazite grade varied between 3% and 6%. The mineralogy investigation included SEM, QEMSCAN and grain counting results, and besides the bulk mineralogy, surface coatings were studied. Surface coatings on both monazite and zircon were highly associated with SiO2, which has previously been detected as a common surface coating in the deposit in the form of opaline silica. SEM and QEMSCAN were used as tools to detect the degree of surface coatings before and after attritioning. It did not conclusively show any effect of the surface attritioning, which therefore remains unknown. Furthermore, the bulk mineralogy of flotation products was studied. It was shown that the concentrates from the tests with high monazite selectivity were enriched in garnets. The oleate collector may therefore be selective for both monazite and garnets at a pH of 10.The key finding of this project is that monazite can be successfully separated from zircon with an oleate collector at a pH of 10. A monazite recovery of 55.6% was possible; however further research into staged flotation to further improve the zircon-rich tail is needed. The results of surface attritioning are not entirely clear, which gives scope for further investigation into mechanical attritioning methods and intensities. Validerat; 20141020 (global_studentproject_submitter)

Samples of amang were collected from Upper Perak, Kinta Valley, Klang Valley and the Pelepah Kanan areas for characterisation, both physically and chemically, using the EPMA (Electronprobe Microanalyser). This preliminary study shows that amang samples from Klian Intan show less ilmenite compared to the other areas. The Klian Intan samples, however, have higher contents of wolframite, pyrite, zircon, arsenopyrite, and rutile. The presence of rooseveltite (BiAs04) is a significant characteristic for the Klian Intan amang. One rooseveltite sample shows inclusions of silica. The amang samples from the Kinta Valley are very rich in ilmenite grains. Studies show 91% ilmenite in amang from Keramat and 93% ilmenite in amang from Air Kuning, and 91 % in amang from Bidor. Struverite (Fex 2(Ta, Nb)2X Ti6().XO.J was found with exsolution bodies of wolframoixiolite ((Nb, W, Ta, Fe, Mn)3 °4) and columbite/tantalite. Wolframoixiolite is a black, opaque, monoclinic mineral. This is the first time it is found in Malaysian amang. Amang from Bidor shows intergrowth relationships of ilmenite with monazite, xenotime and zircon. The studied amang sample from Dengkil, Klang Valley shows the highest content of ilmenite compared to the other areas. It contains 98% ilmenite, 1 % xenotime, and 1 % zircon. On the other hand, the wolframite concentrate from Tekka shows 53% wolframite, 33% ilmenite, 12% silicates, and 2% zircon. EPMA studies of amang sample from Pelepah Kanan shows 81 % iron oxides, 8% silicates, 6% silica, and 5% cassiterite. Abstrak: Sampel amang telah dikutip dari kawasan-kawasan Perak Utara, Lembah Kinta, Lembah Klang dan Pelepah Kanan untuk pencirian, dari segi fizikal dan kimia, dengan dengan menggunakan EPMA (Electroprobe Microanalyser). Kajian awal menunjukkan sampel amang dari Klian Intan adalah kurang ilmenit berbanding dengan kawasan­ kawasan lain. Sampel Klian Intan, walau bagaimanapun, mempunyai kandungan yang lebih tinggi bagi wolframit, pirit, zirkon, arsenopirit, dan ruti!. Kehadiran rooseveltit (BiAs04) adalah satu ciri khas bagi amang Klian Intan. Satu sampel rooseveltit menunjukkan inklusi silika. Sampel amang dari Lembah Kinta adalah sangat kaya dengan butiran ilmenit. Kajian menunjukkan 91% ilmenit di dalam amang dari Keramat dan 93% ilmenit di dalam amang dari Air Kuning, serta 91 % di dalam amang dari Bidor. Struverit ((Fex 2(Ta, Nb)2XTi6().XO.20) telah dijumpai dengan badan-badan eksolusi wolframoixiolit ((Nb, W, Ta, Fe, Mn)P4) bersama-sama dengan columbitltantalit. Wolframoixiolite adalah mineral hitam legap yang bersistem monoklin. Ini adalah pertama kali mineral ini dijumpai di dalam amang Malaysia. Amang dari Bidor menunjukkan hubungan saling pertumbuhan ilmenit dengan monazit, xenotim dan zirkon. Sampel amang yang dikaji dari Dengkil, Lembah Klang menunjukkan kandungan ilmenit yang tertinggi berbanding dengan kawasan-kawasan yang lain. la mengandungi 98% ilmenit, 1 % xenotim, dan 1 % zirkon. Dalam pada itu, padatan wolframite dari Tekka menunjukkan 53% wolframit, 33% ilmenit, 12% silikat, dan 2% zirkon. Kajian EPMA bagi sampel amang dari Pelepah Kanan menunjukkan 81% oksida besi, 8% silikat, dan 5% kasiterit.

vn ÖZET İĞNEADA (KIRKLARELİ) YÖRESİ PLASERLERİNÎN MİNERALOJİK VE JEOKİMYASAL İNCELEMESİ. `İğneada (Kırklareli) Yören Plaserlerinin Mineralojik Ve Jeokimyasal İncelemesi.` Adlı bu çalışma, İ.Ü. Fen Bilimleri Enstitüsü Jeoloji Mühendisliği Ana Bilim Dalı Maden Yatakları ve Jeokimya Programına Doktora Tezi olarak hazırlanmıştır. Istranca Masifi'nin KD kısmında, Demirkaöy İğneada yöresinde yapılan bu çalışmada, bu civardaki Paleozoyik, Mesozoyik ve Senozoyik yaşlı kayaçlardan kaynaklanan birimlerin ağır mineral incelemesi amaçlanmıştır. Bu amaçla Kırklareli E 19 b3, M paftaları tamamen, E 19 a3, bl, b2, el, c2, E 20 al ve a4 paftaları üzerinde yaklaşık 600 km2 'lik bir alanın 1/25000 ölçekli haritası revize edilmiştir. Revize edilen bir alan üzerinde 20 km2 'lik bir MTA ruhsat sahasının 1/10.000 ölçekti detay jeolojik haritası gerçekleştirilmiştir. İnceleme alanında yer alan ruhsat sahası üzerinde derelerden bate sediman numuneleri alınmış, plaserde 17 adet yarma açılmış, bu yarma ve plaserin muhtelif kısımlarından jeokimyasal, mineralojik- petrografik tayin ile binoküler mikroskop kontrolü için numuneler alınmış, jeofizik rezistivite çalışması yapılmış, 3 lokasyonda toplam 282.30 m sondaj çalışması yapılarak yörenin jeolojik yapısı ortaya konulmuş, ayrıca muhtelif derinliklerdeki ağır mineral dağılımı da ortaya konulmuştur. İnceleme alanındaki yapısal unsurlar, Istranca Masifî'nde izlenen ana yapısal yön olan KB-GD yönü ile ikincil KD-GB yönüne uygun olup, jeolojik yapı, granhoyit sokuhımlarımn dizilimi ve eski jeokimya anomalilerinin yayılımı bu yönlere uygundur. Permiyen yaşlı metagranitler, inceleme alanındaki en yaşlı birimler olup, almandin-amfibolit fasiyesinde yüksek dereceli metamorfizma sonucu oluşmuş anateksit granitlerdir. Metagranitler; mesozoik yaşlı retrograt kataklastik metamorfizma sonucu gnaysik granit görünümünde olup, kayma düzlemlerinde şisti doku gösterirler. Bu etkiler sonucunda da bu kayaçlarda diyaftoritik mineraller oluşmuştur. Metagranitler üzerine, Triyas'tan itibaren uyumsuzlukla gelen ve Kretase'ye kadar çökelime devam eden metamorfîk çökel paketi yer alır. Yeşil şist fasiyesinde metamorfjzmaya uğrayan bu kayaçlarda, mineralojik-petrografik incelemeler sonucunda yeşil şist fasiyesinin klorit ve biyotit alt fasiyesîeri görülür. Metamorfik çökel paketi; metaçakıl taşı, metakumtaşı, metakuvarsit, fillit, kalkşist, metagrovak ve dolomitikvm kireçtaşı kayaçlan ile temsil edilir. Bu kayaçlar üzerine yapılan arazi gözlemleri ve petrografik incelemelerde şisti doku iztenilmiştir. Genellikle; metamorfik çökel kayaçlan, Kretase yaşlı granhoyhler tarafından kesilmiş olup, kesme zonlannda kontak metamorfikler izlenir. Bu alanlarda yapılan incelemelerde yoğun skarn mineralleri ve cevherleşme zonlan saptanmıştır. Sokulum kayaçlannda yapılan inceleme ve petrografik tanımlamalar sonucu bunlar, gabro, diorit, kuvars diorit, granodiorit, mikrogranit, ikiztepe graniti ve loko granit olarak 7 bölüme ayrılmışlardır. İnceleme alanının K bölümünde Kretase granhoHlerinin üzerine diskordan olarak üst Kretase yaşlı volkanotortul birimler gelmektedir. Eski çalışmacıların Avcılar çakıkaşı, Rezve formasyonu ve Limanköy formasyonunu ayırtladıklan bu birim bazen tortul seviyelerin (Rezve formasyonu ), bazen de volkanik seviyelerin egemen olduğu (Limanköy formasyonu ) bir yapıdadır. İnceleme alanımızda miyosen yaşlı Çantaköy tüfitİ, Mert formasyonu ve Pliyosen yaşlı Trakya formasyonu en genç çökeller olarak yer almaktadırlar. Bulanıkdere lagününde yapılan S-3 sondajında 60 m derinlikte rastlanılan Priaboniyen yaşlı nummülit fosili içeren İnsaniye formasyonu inceleme alanımızda yüzeylememektedir. Eski ve güncel alüvyonlarla, kumul ve kumsal olarak ayırtlanan Kuvatemer birimleri ağır mineral çalışmalarımız için önem arz etmektedir. İğneada akaçlama havzası ve İğneada plaseri olarak ikiye ayırdığımız inceleme alanımızdaki tüm ağır mineral oluşumlarının Kretase yaşlı sokulum kayaçlan ve yan kayaç dokanaklannda oluşan skarn zonlannda kaynaklandığı, jeomorfolojik verilerle de doğrulanmıştır. Kretase sokulumlanndan Miyosen dönemindeki aşınım şurasında taşman ağır mineraller, önce Neojen birimlerde zenginleşmekte ve daha sonra güncel kumsalda birikmişlerdir. Günümüzde de bu olay Bulanık dere vasıtası ile sürdürülmektedir. Primerde Demirköy, İkiztepe ve Hamdibey civarında, Sivriler köyü doğusunda yer alan Cu-Mo-W cevherleşmelerinin yam sıra buralardan beslenen derelerde ağır mineral zengişlemelerinin varlığı analiz sonuçlan ile doğrulanmıştır. İğneada plaserinde varhğı saptanan Au, Ag, Zr, Ti ve manyetit zenginleşmeleri de keza yine Demirköy batolitinden taşmmışlardır. Buradan alınan örnekler ile bir rezerv vermek kuşkusuz yeterli olmamalıdır. Ancak yapılan çalışma bir rezerv çalışması olmadığından elde edilen sonuçların ortalaması yaklaşık tenor ve rezerv verme açısından yeterli sayılmalıdır. Plaserden başka deniz tabanından da sediman numuneler alınmıştır. Buradanda anlaşılacağı üzere deniz içerisinde de ağır mineral zenginleşmesi mevcuttur. Ancak bu bölümün ağır mineral oranının kumsala göre daha zayıf olduğuK tespit edilmiştir. Buradan hareketle vaktiyle bir lagün olan Mert gülü ve Bulanıkdere'nin iç kesimlerinde ağır mineral oranının artması beklenmelidir. İğneada plaserinde, en çok rastlanılan ağır minerallerden altın, rutil, zirkon ve manyetit bir plaser rezervi oluşturabilecek tenor ve kalitede olduklarından bunlar için daha detaylı çalışmalar yürütülmüştür. Bunlar dışında plaserde görülen diğer ağır mineraller daha ziyade aksesuar özelliğinde olup detaylı incelemesi yapılmamıştır. Bunlar; ilmenit, sfen, granat, monazit, şeelit, kasiterit, apatit, anatas, barit, zinober ve hombled, diopsit, kuvars epidot, dişten, turmalin, piroksen, olivin türü kayaç yapıcı minerallerdir. Sonuç olarak, İğneada Limanı - Mustafa İskelesi sahil şeridinde 40850000 m3 plaser rezervi saptanmıştır. Sahada 0.5 gr/t tenörlü 56 kg altın, 0.034 tenörlü 20813 ton rutil, % 0.0150 tenörlü 9187 ton zirkon ve % 0.5 tenörlü 306.375 ton manyetit rezervinin varlığı tararımızdan saptanmıştır. X SUMMARY THE MDMERALOGICAL AND GEOCHEMICAL INVESTIGATION OF İ?NEADA (KIRKLARELİ) REGION PLACERS This study called `The Mineralogical And Geochemical Investigation Of İğneada (Kırklareli) Region Placers` has been prepaired as Doctorate Thesis for İ.Ü. The Institute of Technical Sciences The Main Scientific Branch of Geological Engineering, The Mineral Deposits and Geochemistry Programme. During die works that are carried out in the Demirköy İğneada that falls in the NE part of the Istranca Massive, the heavy mineral research is aimed for the units generating from the old Paleozoic, Mesozoic and Cenozoic rocks in the above stated area. For such purpose the map of an area of approximately 600 sqkm covering the total part maps of Kırklareli E 19 b3, M, E19 a3,bl,b2,cl c2,E20 al and a4 with a scale of 1/25000 is revised. A comprehensive geological map with a scale of 1/10.000 of the MTA licensed region has been produced within a surface of 20 sqkm in this revised region. The following procedures have been performed in the licensed region which is included in the research area. Stream sediment samples have been collected from the brooks in the region, 17 cleaves have been produced in the placers, for the purpose of binocular microscopic controls specimen have been collected from the various sections of these placers and cleaves with the determination of geochemical, mineralogical-petrography applications, the geophysics resistance determination works have been carried out, The geological formation of the region has been made to come to light by carrying out the works in three locations with an overall drilling work of 282.30 m, as well as the distribution of heavy minerals in various depths have been brought out to light in the region. The formation elements found in the research area conform with the basic formation direction of NW-SE that is tracked in the Istranca massive. The geological formation, the permutation of granitoid texture and the spread of old geochemical anomalies conform with such directions. The permian old metagranites represent the oldest units in the research area and they are actually the basic texture granites that have been produced from high rated metaphors at the facies of almandine - amphibolite. Metagranites; they typically have gneissose texture produced from Mesozoic metamorphism of the old retrograde cataclasis, and they expose schist like texture in their slip planes. Such effects have resulted in the formations of diaphoretic minerals in these rock textures. On the metagranites, the metamorphic sedimentation packet is exposed where its sedimentation is traced from the Triassic down to cretaceous in non-correspondence. The chlorite and biotite sub facies of green schist facies have been found at the end of theXI examinations that are carried out in the mineralogical -petrography level in these rock textures that had been subjected to metamorphism in the green schist facies. The metamorphic sedimentation packet is represented by the rock textures of mete pebbles, meta sandstone, meta quartzite, phyllite, chalk schist, meta graywacke and the dolomitic limestone. The Schist texture is traced on these rock formations during the land surveys and petrography examinations. Generally, the metamorphic sediment rock textures have exposed to be intersected by the quartz like old granitoids, while the contact metamorphous exposures are observed on such intersected zones. The studies that have been carried out in these regions, extensive skarn minerals and ore producing zones have been identified. The studies and petrography researches that have been carried out at the intrusive rocks had displayed the 7 different structures such as; gabbro, diorite, quartz diorite, granodioride, micro granite, the ikiztepe granite and leuco granite. Within the K section of the research area, upper quartz old volcano sediment units have exposed in discordance on the Cretaseous granitoides. This unit which have been identified by the recent researchers in Avcılar pebbles, Rezve Formation and the Limanköy Formation expose a certain structure dominated by either the sedimentation levels(the Rezve formation) or the volcanic level(as is in the Limanköy formation). The Miocene old Çantaköy Tuffs, Mert Formation, and the Pliocene old Thrace formation are found as the youngest sediments in our research region. İnsaniye formation which contains priabomen old nummulites fossil found in the S-3 drilling that is performed in Bulamkdere Lagoon has not exposed on the surface of our research region. The old and new alluvial deposits and dune and sands Quatemers display a significance for our heavy mineral works. All the heavy mineral structures in our research region which is basically divided into two groups as; The İğneada drainage basin and İğneada Placer are generated from the skarn zones that are produced from the cretaceous old intrusive rocks and side rock textures which is also verified by geomorphologic data. The heavy minerals which had been conveyed during the wearing course of the Miocene Period that belongs to the cretaceous intrusive structures have been enriched at the neogene units and then accumulated in the new sands. Currently such event has been continuing through Bulamkdere. Apart from the formation of Cu-Mo-W ores found in the eastern side of the Sivriler Village, the presence of heavy mineral enrichment in the creeks fed in tins area is verified with the results of the current analysis. The enrichments of Au, Ag, Zr, Ti and the magnetite have also been conveyed from this Demirköy batholith. The specimen collected from this area must not be satisfactory to assume an actual reserve at all. Since tile works that have been carried out are not related to any categorical reserve works, thus it must be assumed satisfactory as a matter of approximated substantial tenorXII and reserve. Apart from the placer, some specimens have been collected from sea bed. This clearly indicates that the heavy metal enrichment also exists in the sea bed. On the other hand, the enrichment rate of this section showed to be poorer than the sands. Under the lights of these acts, substantial increase of the mineral rate must be expected in the Mert lake which once has been a lagoon and the inner sections of Bulamkdere. Since the heavy minerals such as; gold, rutile, zircon and magnetite which have been found frequently in İğneada Placer have the quality and the tenor that would likely to produce a placer reserve »further works have been maintained for such heavy minerals. The heavy flmerals encountered other than those mentioned in the preceding paragraph have not been examined in details due to their low rate characters. These are the minerals which form the intrusive textures such as; ilmenke, sphene, garnet, monazite, scheelhe, cassherit metals, apatite, anatase, barite, zinober and the hornblend, diopsite, quartz, epidote, disthene, tourmaline, pyroxene, olivine. Consequently, a placer reserve of 40850000 m3 has been determined in the coast lane of the İğneada Port- Mustafa pier. We have determined 56 kg of gold with a tenor of 0.5 gr/t, 20813 tons of rutile with a tenor of 0.034%, 9187 tons of zircon with a tenor of 0.0150% and 306.375 tons of magnetite with a tenor of 0.5% in the area. 149