Properties
| Category | Sulfide mineral |
|---|---|
| Formula | As2S3 |
| Crystal system | Monoclinic |
| Color | Lemon-yellow to golden or brownish yellow |
| Crystal habit | Commonly in foliated columnar or fibrous aggregates; may be reniform or botryoidal; also granular or powdery; rarely as prismatic crystals |
| Cleavage | Perfect on {010}, imperfect on {100} |
| Tenacity | Sectile |
| Mohs scale hardness | 1.5–2 |
| Luster | Resinous, pearly on cleavage surface |
| Streak | Pale lemon-yellow |
| Diaphaneity | Transparent |
| Specific gravity | 3.49 |
From the Wikipedia article
Orpiment, also known as yellow arsenic blende, is a deep-colored, orange-yellow arsenic sulfide mineral with formula As2S3. It is found in volcanic fumaroles, low-temperature hydrothermal veins, and hot springs and may be formed through sublimation.
Source
Source record: crystal-compendium/orpiment/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Orpiment — revision id 1355037366. Text and properties from Wikipedia, licensed CC BY-SA 4.0.