Editing Internet Texts/Gemstones/Andradite
Andradite
editAndradite is a species of the garnet group. It was named after José Bonifácio de Andrada e Silva (1763-1838), Brazilian politician and mineralogist.
The most valuable variety of andradite is demantoid, also called Uralian emerald. What makes it special are inclusions of actinolite, referred to as horsetail inclusions because of the white or golden color and thread-like shape.[1]
Basic properties
edit| Composition | Ca3Fe2(SiO4)3 |
| Class | Silicates (Neosilicates) |
| Crystal system | Cubic |
| Mohs' hardness | 6,5-7 |
| Fracture | Conchoidal |
| Cleavage | None |
| Lustre | Glassy to adamantine |
| Streak | White |
| Localities | Russia, Italy, Switzerland, USA, China, Namibia |
References
edit- ↑ Minerały i kamienie szlachetne by RBA Collecionables, S.A., ISBN 978-83-7813-150-2, 2012.