Primary minerals like uraninite, coffinite, pitchblende are found below water table while secondary minerals like uranophane
, metatyuyamunite, carnotite are found in the the oxidized environments/above water table hosted by Vihowa group in Sulaiman, Manchar/Vihowa group in Kirthar and Potwar group in Kohat and Potwar basins.
Uranium is found in hundreds of minerals, including uraninite (the most common uranium ore), carnotite, autunite, uranophane
, torbernite and coffinite.
(2015) with X-ray diffraction as meta-autunite (Ca[(U[O.sub.2]).sub.2][(P[O.sub.4]).sub.2x6-8[H.sub.2]O), haiweeite (Ca[(U[O.sub.2]).sub.2][[Si.sub.5][O.sub.12][(OH).sub.2]]x6[H.sub.2]O), uranophane
(Ca[(U[O.sub.2]).sub.2](Hsi[O.sub.4])x5[H.sub.2]O), and metauranospinite (Ca[(U[O.sub.2]).sub.2][(As[O.sub.4]).sub.2]x8[H.sub.2]O).
The secondary uranium mineral, uranophane
, is visible in the host rock in the first few metres of the hole, but below that the rock is apparently unaltered granite with radiometric counts similar to the near surface material.
In the Preit area, uranium prospecting has yielded good specimens of torbernite crystals and of uranophane in aggregates of acicular crystals with barite.
Another uranium mineral locality has been recently found in Val Infemotto, at the far north of the Cuneo Province: zeunerite, autunite, uranospinite and uranophane have been reported from there.
Prospecting in 2007 discovered several outcrops of yellow staining identified as secondary uranium mineral uranophane
along an eight kilometre by 1.5 kilometre east-west corridor.
Recent work including dating of pure secondary uranium phases at Palmottu and another nearby site clearly indicate postglacial mobilization of uranium from primary (mainly uraninite) and secondary uranium phases (uranophane
) in open fractures and the rock matrix and redeposition as uranophane
after very short travel distances downwards (scale of meters) (Read et al., 2004)
Other aesthetic species have also been recovered, including fluorite, quartz, goethite pseudomorphs after siderite, and other important species such as cassiterite, ferberite, metanovacekite, uranophane and metazeunerite.
It yielded a few uranium species, including metanovacekite, metazeunerite and uranophane. Uranium anomalies were previously known from airborne exploration just north of Erongo on the farm Omandumba West 137, at the common boundary with the adjacent Anibib 136 (Roesener and Schreuder, 1992).
The mineral belongs to the uranophane structural group, and is analogous to sklodowskite (with magnesium) and cuprosklodowskite (with copper).
Wherever the black coloring is present in minerals that are usually yellow or orange, there is an excellent likelihood that the radial aggregates resembling sklodowskite and uranophane are in fact oursinite.