What is Tsavorite?
Tsavorite is the green gemstone variety of grossular garnet, coloured mainly by vanadium and sometimes chromium.
Mineralogy and structure
Reference formula: Ca3Al2(SiO4)3. Tsavorite is a grossular variety rather than a separate mineral species. Its green colour, transparency and locality are central to the gem description, while the host garnet structure remains cubic. Tsavorite belongs to the silicates and has a cubic crystal system. The attached COD image is a labelled representative grossular-host model, not a separate tsavorite species lattice. Typical hardness is 6.5–7 on the Mohs scale and specific gravity is approximately 3.5–3.7.
Colour and appearance
Typical colours include bright green, emerald green, yellow-green. The usual dodecahedral, granular, massive habit and vitreous lustre are useful descriptive features, but colour alone is not diagnostic.
Formation and localities
Tsavorite forms in or is associated with calcium-rich skarns and metamorphosed graphitic or impure limestones. Important documented localities include Kenya and Tanzania, with additional East African occurrences. A precise locality and host rock are more useful than a broad colour label.
Collecting notes
Tsavorite 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.
