Origin of Material: AMIS0337 is a commissioned CRM made using ore sourced from the AngloGold Ashanti Limited – Navachab Gold Mine, situated in Namibia, 10km southwest of Karibib and 170km west northwest of Windhoek. The orebody is located in the Central Zone of the Pan-African Damara Orogen. Gold mineralization is hosted by a steeply dipping metamorphosed sequence of interbedded siliciclastic and carbonate rocks. All lithological units contain mineralization to some extent within sheeted quartz veins. The calc-silicate/marble unit (MC) hosts higher-grade replacement skarnoid mineralization.
Mineral and Chemical Composition: The major gangue minerals are dolomite, calcite, feldspar and quartz with minor garnet, hornblende, diopside, ilmenite, biotite and tremolite. Sulphides comprise pyrrhotite; subordinate pyrite, chalcopyrite and traces of bismuth, bismuthinite, sphalerite and galena. Gold occurs as free gold with minor maldonite (gold-bismuth alloy). Approximately ±75% of the gold is <54µ.
Recommended Concentrations and Limits
(at two Standard Deviations)
Au Pb Collection 0.66 ± 0.06 g/t
Specific Gravity 2.88 ± 0.06