AMIS0106 Uranium, alaskite, 114ppm U, Goanikontes, Namibia (215.1 kB)
Recommended Concentrations and Limits
(at two Standard Deviations)
U M/ICP 114 ± 8 ppm
U XRF 122 ± 9 ppm
Specific Gravity 2.65 ± 0.10
S M/ICP 0.056 ± 0.01 %
Origin of Material: This material was supplied by Bannerman Resources Ltd from their Goanikontes Project 30km east of Swakopmund in Namibia. This deposit represents one of the uraniferous alaskite occurrences first actively explored in the Namib Desert during the 1970's. The most significant of these deposits is Rössing Uranium, mined by Rio Tinto since the late 1970's.
The uranium is associated with Lower Palaeozoic age alaskite granites emplaced, predominantly along S3 foliation planes, into heavily folded biotite-amphibole-pyroxene schists of the lower Khan Formation. The term "alaskite" is applied locally to a leucocratric variety of granite, often with a pegmatitic texture.
The most abundant primary uranium mineral is uraninite, but betafite is also present. The uraninite is commonly associated with chloritised biotite in the alaskite. Titanium bearing oxides, ilmenite and magnetite are also present. Goanikites uranium deposit does not show any fundamental qualitative differences compared to the Rössing uranium deposit situated 40 km to the North East.
Mineral and Chemical Composition: Rössing South uranium mineralogy is dominated by uraninite and coffinite, minor brannerite, traces betafite, and the alteration products of the above.