biotite

• Aside from silicate hosts (biotite and hornblende), uraninite is intergrown with pyrrhotite, molybdenite, and zircon. —  Digital50.com Digital 50 Daily Industry News RSS Feed
• The alteration mineral assemblage included pervasive sericite, biotite and pyrite; locally, there are minor amounts of sphalerite, chalcopyrite, galena and arsenopyrite in late veins that cross cut the early synvolcanic alteration. —  StreetInsider.com News Articles
• While the hole did not return significant copper values, the presence of moderate biotite-magnetite and quartz-sericite alteration in the andesite, together with the presence of pyrite throughout the hole, indicates that the Vizcachitas hydrothermal system continues this far south. —  Marketwire - Breaking News Releases
• The biotite flakes must have formed and cooled below 150ºC before the polonium supply was exhausted and the radiohalos could be preserved, so the U decay had to be grossly accelerated and the formation of the plutons had to be within 6-10 days. —  Latest Articles
• The western target, which represents the largest of the chargeability anomalies, coincides in part with an area of tourmaline and secondary biotite alteration, moderate to strong epidote alteration and peripheral quartz-calcite veining. —  Marketwire - Breaking News Releases

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