What is Melanite?
Melanite is a black titanium-bearing andradite variety, usually found in dark crystals associated with alkaline or calcium-rich rocks.
Mineralogy and structure
Reference formula: Ca3(Fe,Ti)2(SiO4)3. Melanite is an andradite-rich variety or variety name, not a separate garnet species. Titanium substitution contributes to its dark colour. Melanite belongs to the silicates and has a cubic crystal system. Typical hardness is 6.5–7 on the Mohs scale and specific gravity is approximately 3.7–4.0.
Colour and appearance
Typical colours include black, brown-black, dark green. The usual dodecahedral, granular habit and vitreous, resinous lustre are useful descriptive features, but colour alone is not diagnostic.
Formation and localities
Melanite forms in or is associated with alkaline igneous rocks, skarns and calcium-rich metamorphic environments. Important documented localities include Italy, Germany, Russia, the United States and Canada. A precise locality and host rock are more useful than a broad colour label.
Collecting notes
Melanite should be labelled as a confirmed species, variety or group-level reference according to the evidence available for the specimen. Record colour, transparency, crystal form, matrix, locality and any treatment history.
