Properties
| Category | Carbonate mineral |
|---|---|
| Formula | FeCO3 |
| Crystal system | Trigonal |
| Color | Pale yellow to tan, grey, brown, green, red, black and sometimes nearly colorless |
| Crystal habit | Tabular crystals, often curved; botryoidal to massive |
| Cleavage | Perfect on {0111} |
| Fracture | Uneven to conchoidal |
| Tenacity | Brittle |
| Mohs scale hardness | 3.75–4.25 |
| Luster | Vitreous, may be silky to pearly |
| Streak | White |
| Diaphaneity | Translucent to subtranslucent |
| Specific gravity | 3.96 |
From the Wikipedia article
Siderite is a mineral composed of iron(II) carbonate (FeCO3). Its name comes from the Ancient Greek word σίδηρος (sídēros), meaning "iron". A valuable iron ore, it consists of 48% iron and lacks sulfur and phosphorus. Zinc, magnesium, and manganese commonly substitute for the iron, resulting in the siderite-smithsonite, siderite-magnesite, and siderite-rhodochrosite solid solution series.
Source
Source record: crystal-compendium/siderite/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Siderite — revision id 1371456304. Text and properties from Wikipedia, licensed CC BY-SA 4.0.