gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1987.051.363.12 Mineralogy Hydrated Copper Oxalate, Moolooite, in Lichens Chisholm J. E. * Jones G. C. * Purvis O. W. † Departments of Mineralogy, British Museum (Natural History), Cromwell Road, London SW7 5BD Botany, British Museum (Natural History), Cromwell Road, London SW7 5BD 12 1987 51 363 715 718 12 11 1986 12 12 1986 Copyright © 1987, The Mineralogical Society 1987 Abstract

Vivid blue inclusions in white whewellite or weddellite, occurring within the medulla of four lichen species growing on copper-bearing rocks, have been identified as the hydrated copper oxalate, moolooite, CuC2O4. nH2O (n ∼ 0.4–0.7), by infrared spectroscopy and X-ray powder diffraction. The mineral is believed to have been formed by reaction between oxalic acid secreted by the lichen and ground or surface water containing copper.

 Keywords moolooite lichens copper oxalate whewellite weddellite