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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

Liversidgeite, ideally [Zn.sub.6][(P[O.sub.4]).sub.4] x 7[H.sub.2]O, is a new mineral from Block 14 Opencut, Broken Hill, New South Wales, Australia. The mineral occurs as white, thin, bladed crystals and as hemispherical aggregates of radiating crystals in cavities in sphalerite-galena ore. Associated minerals are anglesite, pyromorphite, greenockite, sulfur, and an unknown Zn phosphate sulfate. Individual crystals are up to 0.1 mm in length and 0.05 mm across. Liversidgeite is transparent to translucent, with a vitreous luster and a white streak. It is brittle with an irregular fracture, the Mohs hardness is ~3-3.5, and the observed and calculated densities are 3.21(2) and 3.28 g/[cm.sup.3], respectively. Chemical analysis by electron microprobe gave ZnO 54.62, MnO 0.49, PbO 0.18, [P.sub.2][O.sub.5] 32.62, [As.sub.2][O.sub.5] 0.65, S[O.sub.3] 0.35, [H.sub.2]O 14.04, total 102.95 wt%, with [H.sub.2]O content derived from the refined crystal structure. The empirical formula calculated on the basis of 23 O atoms is [Pb.sub.0.01][([Zn.sub.5.86][Mn.sub.0.06]).sub.[SIGMA]5.92] [([P.sub.4.01][As.sub.0.05][S.sub.0.04]).sub.[SIGMA]4.10][O.sub.16.20] x 6.8 [H.sub.2]O. Liversidgeite is triclinic, space group P[bar.1], with a = 8.299(1), b = 9.616(1), c = 12.175(1) [Angstrom], [alpha] = 71.68(1), [beta] = 82.02(1), [gamma] = 80.18(1)[degrees], V = 905.1(2) [[Angstrom].sup.3] (single-crystal data), and Z = 2. The six strongest lines in the X-ray powder diffraction pattern are [d([Angstrom]), (I), (hkl)]: 8.438 (80) (011), 3.206 (60) (01[bar.3]), 2.967 (75) (2[bar.1]2, 114), 2.956 (75) (21[bar.2]), 2.550 (85) (233, 2[bar.1]3), 2.537 (100) (22[bar.1],01[bar.4], 31[bar.1]). The crystal structure of liversidgeite was refined to an R1 index of 5.95% based on 3054 observed ([F.sub.o] > 4[sigma][F.sub.o]) reflections measured with MoK[alpha] X-radiation. The structure is based on two distinct, infinite zigzag chains of edge-sharing Zn[[phi].sub.6] ([phi] = unspecified anion) octahedra that extend in the a direction. The chains link to each other via common corners and also via corner-sharing P[O.sub.4] tetrahedra, forming sheets parallel to the (011) plane. The sheets link via [[Zn.sub.2][[phi].sub.8]] dimeric building units, comprising edge-sharing Zn[[phi].sub.5] trigonal bipyramids and Zn[[phi].sub.4] tetrahedra, resulting in an open framework. Large ellipsoidal channels extend along the a direction and are occupied by interstitial [H.sub.2]O groups and the H atoms of the [H.sub.2]O groups that coordinate to the Zn cations. An extensive network of hydrogen bonds provides additional linkage between the sheets in the structure, via the interstitial [H.sub.2]O groups. The topology of the liversidgeite structure is identical to that of synthetic, monoclinic [Zn.sub.2][Co.sub.4][(P[O.sub.4]).sub.4][([H.sub.2]O).sub.5] x 2[H.sub.2]O. Keywords: Liversidgeite, new mineral species, zinc phosphate, crystal structure, Broken Hill, New South Wales, Australia DOI: 10.2138/am.2010.3306