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Holtite: a new mineral allied to dumortierite

Published online by Cambridge University Press:  05 July 2018

M. W. Pryce*
Affiliation:
Government Chemical Laboratories, Perth, Western Australia

Summary

Holtite, a new mineral allied to dumortierite, occurred as pebbles with stibiotantalite and tantalite on an alluvial tin lease near Greenbushes, Western Australia, and is named after the late H. E. Holt, Prime Minister of Australia.

The mineral is orthorhombic with a 11·905 Å, b 20·355 Å, c 4·690 Å, space group Pmcn, weak supercell 2a, 2b, c developed. Crystals are elongated along c, D 3·90 ± 0·02, hardness 8½, fluorescent. Optical properties α 1·743−1·746, mainly yellow, ‖ [001], β 1·756−1·759, colourless, γ 1·758−1·761, colourless, 2Vα 49−55°, r < v. X-ray powder data are given.

Chemical analysis gave SiO2 20·30, Sb2O5 4·61, Al2O3 46·43, Ta2O5 11·24, Nb2O5 0·76, Fe2O3 0·27, MnO 0·05, TiO2 0·09, BeO 0·05, B2O3 1·82, Sb2O3 13·89, H2O+ 0·38, H2O 0·08, sum 99·97%. On a water-free basis the unit cell contains Al24·5Sb2·56Ta1·36Sb0·76vNb0·16Fe0·10Be0·05Ti0·03Mn0·02B1·40Si9·09O66·85. Compared with dumortierite, 4[(A1,Fe)7BSi3O18] or 4 (X11O18), the holtite unit cell contains approximately 4(X10O17).

Type material is preserved at the Government Chemical Laboratories, Perth, Western Australia.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1971

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References

Bannister, (F.A.) and Hey, (M.H.), 1938. Min. Mag. 25, 30.[M.A. 7-583.]Google Scholar
Buerger, (M.J.), 1960. Crystal Structure Analysis, 242, New York, London (John Wiley) [M.A. 15-252].Google Scholar
Claringbull, (G.F.) and Hey, (M.H.), 1958. Min. Mag. 31, 901.[M.A. 12-57].Google Scholar
Ellsworth, (H.V.), 1928. Ibid. 21, 431.[M.A. 3-602].Google Scholar
Golovastikov, (N. I.) [Foaobacwmcob, (H. H.)], 1965. [Ikova. Akai. Hayn CCCP 162, 1284.] Soviet Physics—-Doklad. 10, 439.[M.A. 17-736].Google Scholar
Gaows, (A.W.), 1949. Silicate Analysis, 2nd edn, 184 London (George Allen and Unwin Ltd.) [M.A. 11-362].Google Scholar
Hartman, (P.), 1969. Min. Mag. 37, 366.10.1180/minmag.1969.037.287.09CrossRefGoogle Scholar
Hey, (M.H.), 1939. Ibid. 25, 402.[M.A. 7-611].Google Scholar
Hey, (M.H.), 1954. Ibid. 30, 481.[M.A. 12-505].Google Scholar
Hobson, (R.A.) and Matheson, (R.S.), 1949. Bull. Geol. Soc. Western Australia, no. 102, 150.Google Scholar
Parker, (R.L.) and Fleiscner, (M.), 1968. U.S. Gëol Surv. Prof Paper no. 612.Google Scholar
Ridgway, (R.), 1912. Colour Standards and Colour Nomenclature Baltimore (A. Hoen and Co.).CrossRefGoogle Scholar
Vlasov, (K.A.) [BAacoB (K. A.)], 1964. Geochemistry and Mineralogy of Rare Elements and Genetic Types of their Deposit. 1, 395.(trans. LERMAN, Z.) Jerusalem (Monson, S.) [M.A. 17-14].Google Scholar