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high textural maturity: very well sorted, well rounded, black, greenish, hyaline shining, smooth and dull, rough-textured surfaces, medium sand (250 to 400 μm)
Thin sections:
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Bright field | Dark field |
mostly coarse VRF (basaltic mikrolithes, ignimbrites), in addition phx of clinopyroxene, olivine, opaque ores (magnetite), epidote, microcline
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