Ilvaite
Mineral CaFe3(Si2O7)O(OH)
Also called Lievrite and Yenite
About it
Jet-black, striated prisms with a submetallic shine in skarns; named for Elba (Ilva in Latin), with fine crystals from Dalnegorsk, Russia, and Huanggang, China.
- Type
- Mineral
- Group
- Silicate (sorosilicate), ilvaite group
- Formula
- CaFe3(Si2O7)O(OH)
- Hardness (Mohs)
- 5.5–6
- Specific gravity
- 3.99–4.05
- Streak
- greenish or brownish black
- Lustre
- submetallic
- Crystal system
- Monoclinic
- Colours
- black, greyish black
- Transparency
- opaque
- Cleavage and fracture
- distinct in one direction
Typical values: real specimens vary. For more, see mindat.org.