Location:

Uranium-rich ores. Port Radium, Northwest Territories, Canada

Uranium ores with by-product radium and silver were mined until 1960. The ores occur as veins within faults and shear zones cutting cherry sediments of the Lower Echo Group, close to biotite granite and granodiorite. The mineralization is multistage and comprises early haematite and quartz followed by pitchblende, haematite and quartz; by quartz, cobalt-nickel arsenides and sulphides; by copper sulphides with chlorite and carbonates; and a final silver, bismuth, chalcopyrite-rich stage associated with carbonates. Argillization, chloritization, haematitization and carbonatization of the wallrocks are associated with the mineralization. The assemblage is very complex, with over forty recorded ore minerals and is essentially the same as that of the Camsell River area.

Major Minerals:

Uraninite (Pitchblende), haematite, chalcopyrite, niccolite, rammelsbergite, skutterudite, native silver

Minor and Trace Minerals:

Include lollingite, tetrahedrite, bornite, chalcocite, sphalerite, galena, marcasite, acanthite, magnetite, coffinite, native bismuth

Textures:

Pitchblende is collomorphic, dendritic and botryoidal, forming 'blasenblende' within quartz and carbonates. It forms rims around wallrock clasts but is fractured and cemented by later sulphides

References:

Campbell, 1957; Robinson and Morton, 1971; Robinson and Ohmoto, 1973; Miller, 1982