The name staurolite comes from the Greek word for cross, stauros because it is often found as cruiciform (cross) twins. The two types of twins are the St. Andrews cross (two staurolite crystals intersect each other at 60o) and the Iron Cross (the crystals intersect each other at 90o).
| (Fe,Mg,Zn)2Al9(Si,Al)4O22(OH)2 |
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| Nesosilicates |
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| Monoclinic |
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| 2/m |
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| 7-7.5 |
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| 3.71 |
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| {010} distinct |
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| Sub-conchoidal |
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| Brownish-yellow/black/red |
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| Gray |
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| Vitreous |
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| Translucent/opaque |
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| Tabular |
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| Notable Localities: |
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| Uses: |
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Specimens:
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