0.8x0.6x0.3 mm hexagonal dipyramidal-pinakoidal crystal of osmium with very widespread composition (Os.51Ir.42Ru.07) - according to L. Cabri classification it had belong to iridosmine compositional field, but according to 50% rule, accepted by IMA, it is osmium now. The crystal is composed by hexagonal dipyramide and pinacoids. Note skeletoidal features of the crystal. They say to us, that the crystal is hydrothermal-metasomatic origin rather than primary magmatic one and had grow from unsaturated fluid/solution. Pavel M. Kartashov collection and photo.
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