Cordierite
Cordierite is a mineral with the chemical formula Mg2Al4Si5O18. It has a Mohs hardness of 7 - 7.5 and vitreous to dull luster.
Cordierite properties
| Type | Mineral |
|---|---|
| Chemical formula | Mg2Al4Si5O18 |
| Mohs hardness | 7 - 7.5 |
| Luster | Vitreous to dull |
| Typical colors | Typically blue, gray, or brown; can also be colorless |
| Formation | Forms in metamorphic rocks, especially in regions of high-grade metamorphism |
| Rarity | 6 / 10 |
Mohs hardness 7–7.5 — hard
1 · Talc5 · Apatite10 · Diamond

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