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epidote
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epidote Figure 42: Granitic rock consisting of reddish orange feldspar, nearly white quartz, and green epidote that appears to have been introduced into an original quartz-feldspar granite. This rock, sometimes called unakite, is used widely in jewelry.
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Basalt sample returned by Apollo 15, from near a long sinous lunar valley called Hadley Rille. Measured at 3.3 years old.
(Bed) Rocks and (Flint) Stones
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epidote
epidote Epidotes are silicate minerals that can be colourless to green or yellow-green.

epidote

mineral
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epidote, any of a group of colourless to green or yellow-green silicate minerals with the general chemical formula A2B3(SiO4)(Si2O7)O(OH), in which A is usually calcium (Ca), though manganese (Mn) or cerium (Ce) is sometimes substituted, and B is generally aluminum (Al), with the main substitution being ferric iron (Fe+3). Structurally, the epidote group consists of chains of AlO6 and Al4(OH)2 octahedra linked by independent SiO4 and Si2O7 groups. The A atoms are in eightfold coordination...

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