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 of Orpiment displays a vibrant golden-yellow to orange color, forming a dense mass with a characteristic resinous to pearly luster on its cleavage surfaces.
Orpiment Physical Properties
Mohs Hardness
1.5Crystal System
monoclinicLuster
resinousStreak Color
pale yellowCleavage
perfect on {010}Fracture
unevenSpecific Gravity
3.49Colors
golden-yellow, orange-yellow, lemon-yellowTransparency
translucentType Locality
Jozankei, Sapporo, Hokkaido Island, JapanMineral Group
sulfidesUses
collector, historical pigmentAssociated Minerals
realgar, arsenic, stibnite, calcite, barite, gypsumRarity
uncommonGeological Context
Orpiment is a low-temperature hydrothermal mineral, typically found in hot spring deposits, volcanic fumaroles, and as an alteration product of other arsenic minerals, often associated with realgar.
