silicates
Grossular
Ca3Al2(SiO4)3
- Also known as
- tsavoritehessoniteTransvaal jade
- Crystal system
- cubic
- Hardness
- 6.5–7 on the Mohs scale
- Lustre
- vitreous
- Colour
- Green, yellow, orange, cinnamon brown, colourless
- Where it forms
- In metamorphosed impure limestones, where calcium from the limestone met aluminium from clay impurities.
- Chiefly from
- KenyaTanzaniaMexicoQuebec, Canada
Why it is that colour
Chromium and vanadium give the green of tsavorite; iron gives the browns and yellows. Pure grossular is colourless.
Safety
Safe to handle.
Where it comes from
Tsavorite comes from a narrow geological belt running through Kenya and Tanzania, worked largely by small-scale miners in difficult conditions. Massive green grossular from South Africa is sold as Transvaal jade.
Historical use
Hessonite, the cinnamon-orange variety, is one of the nine gems of Vedic astrological tradition, where it is called gomed. Tsavorite was found in 1967 and named by Tiffany.
Recorded as history and attributed where possible. That a stone was used for something establishes that people used it, not that it worked.
What is attributed to it, and since when
Named in 1808 from the botanical Latin for gooseberry, after the pale green colour of the original Siberian material. No pre-modern attribution of its own.
Described, not endorsed. Dating a claim is not the same as assessing it — but an association that first appears in a book published in 1985 is not an ancient inheritance, whatever the label says. A sincere account of feeling better is compatible with the stone doing nothing — see the placebo effect.
Sold as this, but not
Worth knowing
Tsavorite is a good test of how much of a gem's value is the material and how much is the story. It is greener than most emerald, harder, tougher, almost never treated, and considerably rarer. It sells for a fraction of the price.
Emerald has three thousand years of accumulated reputation. Tsavorite was found in 1967 by a Scottish geologist named Campbell Bridges, named after Tsavo National Park by Tiffany's Henry Platt, and has had sixty years. That difference is the price difference.
Identity checked against IMA-CNMNC master list, June 2025.