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BIOTITEK(Mg,Fe2+)3(AI,Fe3+)Si3010(OH,F)2

Environment: Mesothermal

 Alteration: Potassic, Potassium Silicate

 

CharacteristicsOutcrops affected by biolite alteration are commonly brown with a purple to red hue. Biotilealteration may occur as vein envelopes, pervasively in shear zones, or as par! of a mixedalteration zone of varied width (commonly >5 m wide alon veins or shear zones. Biolite iscommonly foliated, and may be interlayered with chlorilc, muscovite"sericite, amphiboles or carbonates.

Hand Specimen; Bioute #s blac$, bravm

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tlas o Alteration/