gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1986.050.356.14 Mineralogy Spheniscidite, a New Phosphate Mineral from Elephant Island, British Antarctic Territory Wilson M. J. Bain D. C. Department of Mineral Soils, the Macaulay Institute for Soil Research, Craigiebuckler, Aberdeen 6 1986 50 356 291 293 22 11 1985 Copyright © 1986, The Mineralogical Society 1986 Abstract

Spheniscidite is a new phosphate mineral occurring in a soil profile in an area of nesting penguins on Elephant Island. It is the NH4-dominant analogue of leucophosphite and has the formula (NH4,K)(Fe3+,Al)2 (PO4)2(OH) · 2H2O. It is monoclinic, P21/n with unit cell parameters a = 9.75, b = 9.63, c = 9.70 Å, β = 102° 34′, and Z = 4. The strongest X-ray lines are 6.79(100), 5.99(90), 3.05(45), 7.62(40) Å. Spheniscidite is thought to have formed by the interaction of ammonium phosphate solutions from penguin guano with micaceous and chloritic minerals in the soil. The name is for Sphenisciformes, the order name for penguins, and has been approved by the IMA Commission on New Minerals and Mineral Names.

 Keywords spheniscidite phosphate minerals new minerals Elephant Island Antarctica