Melanite
Variety Ca3(Fe,Ti)2(SiO4)3
About it
Black, titanium-rich andradite garnet, found as glossy dodecahedra in alkaline igneous rocks and skarns. Known from the volcanic districts of Italy and from Magnet Cove, Arkansas.
- Type
- Variety
- Group
- Andradite variety (garnet)
- Formula
- Ca3(Fe,Ti)2(SiO4)3
- Hardness (Mohs)
- 6.5–7
- Specific gravity
- 3.7–4.1
- Streak
- white
- Lustre
- vitreous (glassy), adamantine (diamond-like)
- Crystal system
- Isometric (cubic)
- Colours
- black
- Transparency
- opaque
- Cleavage and fracture
- none; conchoidal to uneven fracture
Typical values: real specimens vary. For more, see mindat.org.