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Defines geodiversity, compares it to biodiversity, and discusses the mineral classification system. Charts the discovery of new minerals in Australia over time and focuses on uses of these minerals in technological advances. (DDR)

Kapundaite, ideally [(Na,Ca).sub.2][Fe.sup.3+.sub.4][(P[O.sub.4]).sub.4] [(OH).sub.3] x 5[H.sub.2]O, is a new mineral (IMA2009-047) from Toms phosphate quarry, Kapunda, South Australia, Australia. The new mineral occurs as cavernous aggregates of fibers up to several centimeters across, associated with leucophosphite, natrodufrenite, and meurigite-Na crystals and amorphous brown, black, and/or greenish coatings. Individual kapundaite crystals are very thin flattened fibers up to a few millimeters in length, but typically no more than a few micrometers in thickness. The main form observed is {100}; other forms in the [010] zone are present, but cannot be measured. Crystals of kapundaite are pale to golden yellow, transparent to translucent, have a yellow streak and silky luster, and are non-fluorescent. Mohs hardness is estimated to be about 3; no twinning or cleavage was observed. Kapundaite is biaxial (+), with indices of refraction [alpha] = 1.717(3), [beta] = 1.737(3), and [gamma] = 1.790(3). 2V could not be measured; [2V.sub.cale] is 64.7[degrees]. The optical orientation is Z = b, Y [approximately equal to] c with weak pleochroism: X= nearly colorless, Y= light brown, Z = pale brown; absorption: Y> Z > X. No dispersion was observed. The empirical chemical formula (mean of seven electron microprobe analyses) calculated on the basis of 24 O is ([Ca.sub.1.13][Na.sub.0.95])[summation]2.08[([Fe.sup.3+.sub.3.83] [Mn.sub.0.03][Al.sub.0.02][Mg.sub.0.01]).sub.[summation]3.89] [P.sub.3.92][O.sub.16]([OH).sub.3] x 5[H.sub.2.11]O. Kapundaite is triclinic, space group P[bar.1], a = 6.317(5), b - 7.698(6), c = 9.768(7) [Angstrom], [alpha] = 105.53[(1).sup.o], [beta] = 99.24[(2).sup.o], [gamma] = 90.09[(2).sub.o], V = 451.2(6) [[Angstrom].sup.3], and Z- 1. The five strongest lines in the powder X-ray diffraction pattern are [[d.sub.obs] in [Angstrom], (I) (hkl)]: 9.338 (100) (001 ), 2.753 (64) (2[bar.1]1), 5.173 (52) (011 ), 2.417 (48) ([bar.2][bar.1]-3, 202, 0[bar.1]4), and 3.828 (45)(0[bar.2]1). The crystal structure was solved from single-crystal X-ray diffraction data using synchrotron radiation and refined to [R.sub.1] = 0.1382 on the basis of 816 unique reflections with [F.sub.o] > 4[sigma]F. The structure of kapundaite is based on a unique corrugated octahedral-tetrahedral sheet, which is composed of two types of chains parallel to a. Kapundaite is structurally related to melonjosephite. The mineral is named for the nearest town to the quarry. Keywords: Kapundaite, new mineral, phosphate, Toms phosphate quarry, crystal structure, octahedral-tetrahedral sheet, melonjosephite DOI: 10.2138/am.2010.3466

Coulsellite, Ca[Na.sub.3]Al[Mg.sub.3][F.sub.14], from the Cleveland tin mine at Luina, western Tasmania, has a rhombohedral distortion of the cubic pyrochlore [A.sub.2][B.sub.2][X.sub.6]Y structure, with a = 7.1756(1) [Angstrom], [alpha] = 59.867[(1).sup.o], space group R[bar.3]m, Z = 1. The corresponding hexagonal cell parameters are a = 7.1620(1) [Angstrom], c = 17.5972(3) [Angstrom]. The crystals are multiply twinned about threefold axes of the pseudocubic cell. The structure was determined using X-ray data collected on a twinned crystal and refined to Robs = 0.027 for 452 observed reflections with 1 > 2[sigma](I). The structure is possibly unique among published structures of pyrochlore-like minerals in having full 1:3 ordering of Ca:Na in the A sites and Al:Mg in the B sites. Transmission electron photomicrographs show a nanodomain structure due to twinning on a scale of ~5 nm. Keywords: Rhombohedral pyrochlore, new fluoride mineral, structure determination, 1:3 cation ordering in Ca[Na.sub.3]Al[Mg.sub.3][F.sub.14] DOI: 10.2138/am.2010.3360

The crystal structure of a natural Na-rich gobbinsite from Bundoora, a northern suburb of Melbourne, Victoria, Australia [[([Na.sub.4.97] [K.sub.0.07][Ca.sub.0.48]).sub.[SIGMA]5.52][([Al.sub.5.62] [Si.sub.10.29]).sub.[SIGMA]15.91][O.sub.32]* 11.91[H.sub.2]O, Z = 1, a = 10.1035(15), b = 9.7819(10), c = 10.1523(9) [Angstrom], and V = 1003.37(20) [[Angstrom].sup.3], space group Pmnb (no. 62)], has been investigated by means of single-crystal X-ray diffraction, elemental CHN analysis, and electron microprobe analysis in the wavelength dispersive mode. For the first time, an anisotropic structural refinement has been performed on the basis of single-crystal X-ray diffraction data collected at 298 K, with: [R.sub.1](F) = 0.0608, 1362 unique reflections with [F.sub.o] > 4[sigma]([F.sub.o]), and 114 refined parameters. The residuals in the final difference-Fourier maps are less than [+ or -] 0.6 e-/[[Angstrom].sup.3]. Previous structure solutions based on powder diffraction data were performed in the space group [Pmn2.sub.1], with a significantly different description of the channels' content. In this study, the Si/Al distribution in the tetrahedral framework is found to be highly disordered. A complex configuration of the extra-framework population occurs, with two possible and mutually exclusive sites for cations (Na and Ca) and five independent sites partially occupied by water molecules (W1, W2, W2', W3, and WY). The coordination shell of the Na site is represented by a distorted polyhedron with coordination number CN = 6 (4 framework O atoms + 2 [H.sub.2]O molecules), with at least five possible mutually exclusive configurations, whereas the coordination shell of the Ca site is represented by a distorted polyhedron with CN = 7 (5 framework O atoms + 2 [H.sub.2]O molecules), with at least two possible mutually exclusive configurations. Keywords: Zeolite, gobbinsite, Bundoora (Victoria), crystal structure, single-crystal X-ray diffraction DOI: 10.2138/am.2010.3390

Kintoreite, Pb[Fe.sub.3][H.sub.0.94][[[(P[O.sub.4]).sub.0.97] [(S[O.sub.4]).sub.0.03].sub.2][(OH).sub.6], and zincian kintoreite, Pb[Zn.sub.0.3][Fe.sub.3][H.sub.0.24][[[(P[O.sub.4]).sub.0.54] [(S[O.sub.4]).sub.0.08][(As[O.sub.4]).sub.038]].sub.2][(OH).sub.6], have rhombohedral symmetry, space group R[bar.3]m, with hexagonal cell parameters a = 7.2963(5) [Angstrom], c = 16.8491(5) [Angstrom], and a = 7.3789(3) [Angstrom], c = 16.8552(7) [Angstrom], respectively. The structures have been refined using single-crystal X-ray data to [R.sub.1] = 0.030 for 374 observed reflections and [R.sub.1] = 0.035 for 399 observed reflections, respectively. The structures of both minerals comprise rhombohedral stacking of (001) composite layers of corner-shared octahedra and tetrahedra with Pb atoms occupying icosahedral sites between the layers, as in the alunite-type structure. The corner-connected octahedra form three-membered and six-membered rings as in hexagonal tungsten bronzes. The structure of zincian kintoreite differs from other alunite-type structures in having partial occupation, by Zn, of new sites within the six-membered rings in the octahedral layers. The Zn is displaced to an off-center position in the hexagonal ring, where it assumes fivefold trigonal-bipyramidal coordination, to three of the hydroxyl anions forming the ring, and to the apical O anions of the X[O.sub.4] tetrahedra on opposite sides of the ring. The different structural modes of Zn incorporation into S[O.sub.4]-dominant and (P, As)[O.sub.4]-dominant members of [A.sup.2+][B.sup.3+.sub.3] [(X[O.sub.4]).sub.2][(OH).sub.6] alunite-type minerals are discussed in terms of the different charge-compensation mechanisms involved. Keywords: Zincian kintoreite, crystal structure, alunite-type structure, single-crystal study

Lakebogaite, ideally CaNa[Fe.sup.3+].sub.2]H[(U[O.sub.2]).sub.2] [(P[O.sub.4]).sub.4][(OH).sub.2][([H.sub.2]O).sub.8], is a new Ca-Na-Fe uranyl phosphate mineral from a quarry in Upper Devonian granite near Lake Boga, northern Victoria, Australia. It is associated with Na-analogue of meurigite (IMA 2007-024), torbernite, and saldeite on a matrix ofmicrocline, albite, smoky quartz, and muscovite. Lakebogaite occurs as bright lemon-yellow transparent prismatic crystals up to 0.4 mm across. The crystals have a vitreous luster and a pale yellow streak. Mohs hardness is about 3. The fracture is even to conchoidal. In transmitted light, the mineral is pale yellow with very weak pleochroism: X = yellow, Y = grayish yellow, Z = grayish yellow: dispersion r > v, strong. Lakebogaite crystals are biaxial (+), with slightly variable refractive indices within the ranges: [n.sub.a] - 1.650(2)-1.652(2), [n.sub.[beta]] = 1.660(4)-1.664(3), [n.sub.[gamma]]= 1.681(3)-1.686(2), measured using white light, and with 2 [V.sub.meas] = 80-85[degrees] and 2[V.sub.calc] = 70-74[degrees]. Orientation: Y = b; crystals are elongated along [010], resulting in straight extinction. The empirical chemical formula (mean of nine electron micro probe analyses) calculated on the basis of 30 anions is [([Ca.sub.100]Na.sub.0.80 [Sr.sub.0.10).sub.[SIGMA]1.90][([Fe..sup.3+.sub.1.85] [Al.sub.0.30]).sub.[SIGMA]2.15][(U[O.sub.2]).sub.1.80] [(P[O.sub.4]).sub.4.07][(OH,[H.sub.2]O).sub.10.12]. Lakebogaite is monoclinic, space group Cc, a = 19.6441(5), b = 7.0958(2), c - 18.7029(5) [Angstrom], [beta] - 115.692(1)[degrees], V = 2349.3(7) [[Angstrom].sup.3], Z = 4. The seven strongest reflections in the powder X-ray diffraction pattern are [[d.sub.obs] in [Angstrom] (I) (hkl)]: 6.60 (100) (110), 3.16 (40) (51[bar.4], 60[bar.4]), 4.07 (20) (40[bar.4]), 3.80 (20) (31[bar.4]), 3.56 (20) (020, 312), 3.31 (20) (114, 220), 2.797 (20) (006). The crystal structure was solved from single-crystal X-ray diffraction data and refined to [R.sub.1] = 0.038 on the basis of 5222 unique reflections with F > 4[sigma]F. It comprises pairs of edge-shared U[O.sub.7] pentagonal bipyramids that are inter-linked via corner-sharing with P[O.sub.4] tetrahedra, to form chains parallel to the e-axis. Each U[O.sub.7] polyhedron also shares one of its edges with another P[O.sub.4] tetrahedron. The [(U[O.sub.2]).sub.2][(P[O.sub.4]).sub.4] chains are cross-linked via corner-sharing between the P[O.sub.4] tetrahedra and [Fe.sup.3+] [O.sub.4][(OH).sub.2] octahedra. The octahedrajoin together by corner-sharing via OH anions to form chains parallel to b. The [Na.sup.+] and [Ca.sup.2+] cations, and 4 water molecules occupy eight-sided channels along [010]. The remaining water molecules occupy large ten-sided channels directed along [001] and intersecting the [010] channels. The mineral is named for the nearest township. Keywords: Lakebogaite, new mineral, uranyl phosphate, Lake Boga quarry, north-western Victoria, Australia, crystal structure, [(U[O.sub.2]).sub.2][(P[O.sub.4]).sub.4] chains

The introduction of a fifth amphibole group, the Na-Ca-Mg-Fe-Mn-Li group, defined by 0.50 < [sup.B](Mg,[Fe.sup.2+],[Mn.sup.2+],Li)

Bamfordite from the abandoned W-Mo-Bi mines at Bamford, Queensland, Australia, is a new hydrated iron molybdate with a unique structure. This mineral formed by oxidation of molybdenite, Mo[S.sub.2], in the presence of strongly acidic solutions. It occurs as microcrystalline aggregates of tabular triclinic crystals between 0.005 and 0.05 mm long. The aggregates are apple-green with an earthy luster and greenish yellow streak. Crystals are transparent, with pale to moderate yellow-green pleochrolsm. They show principal forms {001], {100}, {010}, {110}, {110} and prominent (100) cleavage traces. The Mohs hardness is 2-3 and the measured density is 3.620 g/[cm.sup.3] (calculated density is 3.616 g/[cm.sup.3]). Crystals are biaxial negative and length slow, with RIs of [Alpha] = 1,91, [Beta] = 2.03, and [Gamma] = 2.11, and 2V [equivalent] 90 [degrees]. Chemical analysis yielded an empirical formula of [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] [Mo.sub.2.01][W.sub.0.03] [P.sub.0.02] [O.sub.10][H.sub.4.62], calculated on the basis of ten O atoms. The simplified formula is [Fe.sup.2+] [Mo.sub.2],[O.sub.6] [(OH).sub.3] [multiplied by] [O.sub.10] [H.sub.4.62] chosen on the basis of crystal-structure determination and Mossbauer spectroscopy results. Unit-cell parameters calculated both from the X-ray powder and single-crystal diffraction data are a = 5.889(5), b T545(5), c = 9.419(5) [Angstrom]; [Alpha] = 71.46(4) [degrees], [Beta] = 83.421(4) [degrees], [Gamma] = 72.78(4) [degrees]; V = 378.9(4) [[Angstrom].sup.3]; Z = 2; P1 or P1. The crystal structure was solved in P1 using direct methods and Fourier techniques. The final refinement based on 1486 observed reflections [I [is greater than] 2.00 [Sigma]I] converged to R = 0.05 and [R.sub.w] = 0.038. The bamfordite crystal structure contains groups of four Mo[O.sub.6] octahedra, linked by edge-sharing, which in turn are linked through corner-sharing to pairs of Fe[O.sub.6] octahedra thereby forming infinite sheets parallel to (100). These sheets are stepped and linked by hydrogen bonding. No other molybdenum oxides have this or a similar structure, instead molybdates such as wulfenite, PbMo[O.sub.4] are based on tetrahedrally coordinated molybdenum.

The International Mineralogical Association's approved amphibole nomenclature has been revised to simplify it, make it more consistent with divisions generally at 50%, define prefixes and modifiers more precisely, and include new amphibole species discovered and named since 1978, when the previous scheme was approved. The same reference axes form the basis of the new scheme and most names are little changed, but compound species names like tremolitic hornblende (now magnesiohornblende) are abolished, as are crossite (now glaucophane or ferroglaucophane or magnesioriebeckite or riebeckite), tirodite (now manganocummingtonite), and dannemorite (now manganogrunerite). The 50% rule has been broken only to retain tremolite and actinolite as in the 1978 scheme; the sodic-calcic amphibole range has therefore been expanded. Alkali amphiboles are now sodic amphiboles. The use of hyphens is defined. New amphibole names approved since 1978 include nyboite, leakeite, kornite, ungarettiite, sadanagaite, and cannilloite. All abandoned names are listed. The formulae and source of the amphibole end-member names are listed and procedures outlined to calculate [Fe.sup.3+] and [Fe.sup.2+] where not determined by analysis.

Reproduced with permission Bulk uranium contents of several different varieties of Lake Boga fluorapatite crystals were determined by isotope dilution mass spectrometry (Mills [7]). Fluorapatite crystals were first recorded in the Lake Boga Granite, in northern Victoria, Australia, in 1941, some fifteen years after a small quarrying operation was established to crush the granite for aggregate (Hills [6]; Birch [2]). Interpenetrating fluorapatite crystals showing characteristic zoning in blue shades, larger crystal 2.5 cm across, with schorl, Lake Boga. Conclusion The Lake Boga fluorapatite crystals are not only attractive in their own right, but they also preserve a record of fluctuating uranium, manganese, and strontium contents in the late-stage hydrothermal fluids circulating within the upper levels of the cooling granite. [Extracted from the article]

A newly identified occurrence for the rare bismuth-copper phosphate mrazekite has proven to contain other rare bismuth minerals as well, including namibite and schumacherite. INTRODUCTION The bismuth-copper phosphate mineral mrazekite, [...]

Bernalite, a new iron hydroxide mineral from New South Wales, Australia, is a flattened pyramidal or a pseudo-octahedral bottle-green crystal with a vitreous to adamantine luster. An uneven to conchoidal fracture and Mohs hardness of 4 appear in the brittle mineral which has no cleavage. The pseudocubic Bernalite has a crystal structure solved by the Patterson methods, but the effect of polysynthetic twinning prevents full refinement. A three dimensional network of corner-connected octahedra represents the distorted Re O3-like structure. The mineral has been named after the British crystallographer J.D. Bernal.