Preliminary report on the mineralogical occurrence of gold palladium, platinum, uranium and rare earths in heavy liquid fractions, with a note on the occurrence of a rare platinum selenide mineral from DDH5, Coronation Hill, NT.

Abstract

This report is a memorandum from Petrology section of BHP which documents mineragraphy on six sink and float fractions prepared using Clerici Solution (SG 4.05) from drill core from Coronation Hill DDH5. The following mineral phases were identified using optical, SEM, and Microprobe: Gold, including silver bearing variety, stibiopalladinite (Pd5Sb2), native palladium, Bi-Pd-Sb phase, Pt-Pd-?Fe phase, Au-Pd phase, bismuth silver selenide, bismuth palladium selenide, palladium mercury selenide, sudburyite (PdSb), platinum (palladium) selenide, pyrite (some nickeliferous), marcasite, pyrrhotite, clausthalite (PbSe), sphalerite, chalcopyrite, galena, nickel cobalt selenide, nickel cobalt sulphide, bornite, chalcocite, uraninite, uranium yttrium silicate (?yttrian coffinite), florencite ([(Ce,La,Ca) Al3 (PO4)2(OH)6], monazite [(Ce,La) PO4], hematite (colloform and tabular), rutile/ leucoxene, ilmenite, magnetite. This is a preliminary report and later ones are more relevant to mineral dressing, though there is some discussion of the implications of observations. The occurrence of Pt as selenide will render it insoluble in cyanide solution. Uranium mineralisation is closely associated with base metal sulphides.