The primary uranium minerals are uraninite and coffinite but numerous secondary uranium minerals have been formed as a result of the weathering processes: yellow gummites, autunite
, metaautunite, torbernite, saleeite, uranotyle, ianthinite and uranopilite (Arribas, 1975).
The strongly sheared samples (such as sample 139, Table 2) have geochemical characteristics comparable to the mineralized zones containing chalcopyrite, pyrite, sphalerite, and autunite
from the Millet Brook deposit (Chatterjee and Strong 1984), although the alteration intensity and elemental enrichment are much less pronounced in the drill core samples (Table 1).
We found garnets and autunite
, feldspar and lepidolite.
has been reported as a very minor supergene mineral produced by weathering of alteration products of early-stage veins at the Globe Hill mine, and associated with other secondary uranium minerals in Tertiary volcanics (Thompson et al.
Allan's Chilean proustite, Tsumeb dioptase, Tur kish kammererite, Mexican acanthite, Congo cuprite; Ralph's Swiss anatase, Brazilian autunite
, North Carolina hiddenite; both men's Montana veszelyites .
specimens from the Daybreak mine near Spokane, Washington, are notorious for dehydrating and exfoliating or splitting over time.
occurs rarely at Sapucaia, as small crystals perched on (or enclosed in) variscite, and as fissure coatings in albite near johnsomervilleite crystal groups.
Common examples include autunite
and some fluorite, especially the purple/green specimens from Durham, England, which fluoresce blue.
is erroneously quoted in early internal reports; but in fact there is no radioactivity at all in the primary ore.
Agnes, liroconite crystals on matrix from Huel Gorland, beautiful chalcophyllite groups, botryoidal malachite from Wheal Unity, gold nuggets, superb cubic and octahedral cuprite crystals on matrix, lustrous jet-black sphalerite crystals, blue-tarnished chalcopyrite crystals on quartz, torbernite and autunite
crystals, phenakite crystals from St.