Ilvaite

Locality: Rio Marina, Elba Island, Livorno Province, Tuscany, Italy

Field of View: fourteen mm

Formula:
CaFe
2+
2
Fe
3+
 
(Si
 
2
O
 
7
)O(OH)
System: Orthorhombic Colour: Iron-black, nighttime grayish …
Hardness: 5½ – 6

Ilvaite crystal from Mt.Fico. Collection & Photo M.Chinellato


Sumber http://www.geologyin.com