Siderite
| Colour | Brown, Yellow |
|---|---|
| Mohs hardness | 3.75–4.25 |
| Lustre | Vitreous, may be silky to pearly |
| Streak | White |
| Crystal system | Trigonal |
| Transparency | Translucent to subtranslucent |
| Cleavage | Perfect on {011} |
| Fracture | Uneven to conchoidal |
| Chemical formula | FeCO 3 |
| Specific gravity | 3.96 |
What is Siderite?
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.
How to identify Siderite
- Lustre: Vitreous, may be silky to pearly.
- Hardness: Mohs 3.75–4.25 — soft; a knife will scratch it.
- Streak: White.
- Habit: Trigonal crystal system.
Siderite in different forms
Stones often confused with Siderite
Frequently asked questions
How hard is Siderite?
Siderite is Mohs 3.75–4.25 on the hardness scale.
What colour is Siderite?
Siderite is typically brown, yellow (Pale yellow to tan, grey, brown, green, red, black and sometimes nearly colorless).