Tags: Chemical Substance, Mineral.
Alacránite (As8S9) is an arsenic sulfide mineral first discovered in the Uzon caldera Kamchatka Russia. It was named for its occurrence in the Alacrán silver arsenic antimony mine Pampa Larga Chile. It is generally more rare than realgar and orpiment. Its origin is hydrothermal. It occurs as subhedral to euhedral tabular orange to pale gray crystals that are transparent to translucent. It has a yellow-orange streak with a hardness of 1.5. It crystallizes in the monoclinic crystal system.