the transparent yellow mineral arsenic sulfide (As2S3), formed as a hot-springs deposit, an alteration product (especially from realgar), or as a low-temperature product in hydrothermal veins. It is found in Copalnic, Romania; Andreas-Berg, Ger.; Valais, Switz.; and Colemerik, Tur. The crystals belong to the monoclinic system. For detailed physical properties, see sulfide mineral (table)
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