Description
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AMIS0336 Au 0.1 g/t Siliceous Navachab Namibia
Origin of Material
This CRM was commissioned using ore sourced from the AngloGold Ashanti Limited – Navachab Gold Mine, situated in Namibia. 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.
Approximate 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)
Certified Concentrations
Au Pb collection1 0.10 0.01 g/t
As 4A-MICP2 71.1 21 ppm
Cu 4A-MICP2 176 11 ppm
LOI LOI4 25.6 0.20 %
S Comb/LECO5 0.23 0.02 %
SG SG6 2.71 0.11 Dimensionless
