Snow-white ultramicro-fibrous compact gearksutite agregate. It was formed during interaction of HF (produced by pyrite oxidation in fluorite matrix) with concretion of allophane into quartz-muscovite greisen. Associating minerals are quartz crystals and minor muscovite (var. gilbertite). Specimen size is 9x5.5x4 cm. Collected by Victor I. Stepanov in August of 1962 on dumps of vein #1 of the deposit. Pavel M. Kartashov collection and photo.
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