Figure F42. Subtype of hyaloclastite consisting of basalt clasts and altered glassy clasts and glassy shards cemented by quartz, carbonate, and sulfide (mineralized volcanic breccia). A. Thin section (Sample 309-1256D-122R-1 [Piece 19, 140142 cm]) (thin section 80). B. Spherulitic texture in cryptocrystalline basalt clasts of the hyaloclastite (Sample 309-1256D-122R-1 [Piece 16, 119124 cm] (plane-polarized light, blue filter; field of view = 5 mm; thin section 78). Light spots are sulfides.
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