Properties
| Category | Sulfide mineral |
|---|---|
| Formula | Mercury(II) sulfide, HgS |
| Crystal system | Trigonal |
| Color | Cochineal-red, towards brownish red and lead-gray |
| Crystal habit | Rhombohedral to tabular; granular to massive and as incrustations |
| Cleavage | Prismatic {1010}, perfect |
| Fracture | Uneven to subconchoidal |
| Tenacity | Slightly sectile |
| Mohs scale hardness | 2.0–2.5 |
| Luster | Adamantine to dull |
| Streak | Scarlet |
| Diaphaneity | Transparent in thin pieces |
| Specific gravity | 8.176 |
From the Wikipedia article
Cinnabar, also called cinnabarite or mercurblende, is the bright scarlet to brick-red form of mercury(II) sulfide (HgS). It is the most common source ore for refining elemental mercury and is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments.
Source
Source record: crystal-compendium/cinnabar/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Cinnabar — revision id 1364136825. Text and properties from Wikipedia, licensed CC BY-SA 4.0.