Another very rare Tanzanian gemstone is tsavorite garnet, which was discovered by British gem prospector Campbell R Bridges in 1967. By following the seam north of the Tanzania/Kenya border, a couple of years later he discovered green garnet in Kenya too. It’s no surprise therefore that it’s the same seam that overlaps where tanzanite is found, at the foothills of Kilimanjaro in Merelani.
During our gemstone tour, we were taken to a green garnet mine, also a source for tourmaline, in Umba (100km north of Tanga).
A good example of an artisanal mine, this was one of those caves with a 3ft x 5ft opening, which became even narrower as you went down, forcing you to crawl on your hands and feet. I found it easier to slide down on my backside. It was dusty and pitch black, with no ventilation. My headtorch was playing up, so I was guided by the headtorch in front of me – which occasionally disappeared around a corner, leaving me in the dark!
The hardcore amongst us made it to the bottom, where space was extremely tight. It wasn’t long before I could feel claustrophobia setting in. My eyes were stinging from dust and perspiration, but I just about managed to hold out long enough to see the seam of green garnet and scrape a small sample of crystals.
Green garnet, also known as tsavorite, is a variety of the species grossular garnet, getting its colour from vanadium or chromium. It has a wonderful transparency with a beautiful rich glow which (in my opinion) rivals the glow of any Muzo Colombian emerald. I have to admit that I found myself falling in love with tsavorite and wanted to bring a souvenir back home, but after several visits to the gemstone markets, I could only find tsavorite crystals in very small sizes: mostly below 0.5 carat. Rarely did I see a raw tsavorite crystal over a carat. Its astronomical price could be attributed to its extreme scarcity, rarity, and the gruelling mining process required to extract it.
That said, I did see a few extraordinary tsavorites later in my trip, in the retail jewellery shops in Dar es Salaam. Buying ready-made jewellery in Tanzania is a completely different proposition to buying rough gemstones directly with the traders at the market, of course. If you’re not in Tanzania buying gemstones for business (which requires a business visa and following strict export rules), buying from a reputable shop is definitely the best way to purchase a piece of tsavorite jewellery to take home as a memory.
If you had to make a choice between tanzanite or tsavorite as a souvenir of your holiday, it might help you to know that whilst tsavorite is much more expensive than tanzanite, tsavorite is slightly harder than tanzanite on the Mohs scale, meaning that it is more durable and harder to scratch. That said, you would still need to take good care of your tsavorite jewellery.
Here are a few photostaken inside the Tsavorite garnet mine:
If you're eager to join me on an educational journey to Tanzania, be sure to check out our exclusive gemstone discovery tour, set to depart in July 2024!
Kim Rix, GG GIA
Be sure. Be smart. Buy with confidence