from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A yellowish, fluorescent minor ore of uranium with the composition Ca(UO2)2(PO4)2·10-12H2O.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A yellow mineral with tetragonal crystals, Ca(UO2)2(PO4)2·10-12H2O.
from the GNU version of the Collaborative International Dictionary of English
- n. A lemon-yellow phosphate of uranium and calcium occurring in tabular crystals with basal cleavage, and in micalike scales. H., 2-2.5. Sp. gr., 3.05-3.19.
from The Century Dictionary and Cyclopedia
- n. A native hydrous phosphate of uranium and calcium, occurring in tabular crystals, nearly square in form, and of a citron or sulphur-yellow color.
The mica does not everywhere present this coarsely crystalline appearance, but in flexures and lines of union with the quartz and orthoclase is degraded to a mica schist upon whose surfaces appear uranates of lime and copper (autunite and torbernite), and in which are inclosed garnet crystals of considerable size and beauty.
He already knew ore -- the glossy, sub-metallic, pitchy black luster of uraninite or pitchblende; the yellows of autunite and carnotite; the variant and confusing greens of tobernite.
The radium-bearing minerals are torbernite and autunite (hydrous copper-uranium and calcium-uranium phosphates), and are found in dark felsite dikes near their intersections with east-west gold-silver-quartz veins.
But an unexpected fact was noted: certain minerals (pitchblende, chalcolite, autunite) had a greater activity than might be expected on the basis of their uranium or thorium content.
Over 150 minerals: mica, feldspar, beryl, amethyst, rose / smokey quartz, garnet, and Uranium minerals (gummite, autunite) prized by collectors / museums.
; and as phosphate in the uranites, torbernite (hydrated phosphate of uranium and copper), and autunite (hydrated phosphate of uranium and lime).
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