Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
monoclinicuncommonsulfides
Orpiment
As₂S₃
This specimen features bright lemon-yellow, foliated masses of orpiment, often with a pearly luster on cleavage surfaces, contrasting with the white baryte.
Orpiment Physical Properties
Mohs Hardness
1.5Crystal System
monoclinicLuster
resinousStreak Color
pale yellowCleavage
perfect on {010}Fracture
conchoidalSpecific Gravity
3.49Colors
lemon-yellow, golden-yellow, brownish-yellowTransparency
translucentType Locality
El'brusskiy (Elbrusskii) Arsenic mine, Elbrus, Kabardino-Balkarian Republic, Northern Caucasus, RussiaMineral Group
sulfidesUses
collector, historical pigment, arsenic oreAssociated Minerals
baryte, realgar, stibnite, cinnabarRarity
uncommonGeological Context
Orpiment forms in low-temperature hydrothermal veins, hot springs, and volcanic fumaroles, typically in arsenic-rich environments. It is often found as an alteration product of other arsenic minerals like realgar.
