Tsavorite is grossular garnet coloured by vanadium and chromium, discovered in the Tsavo game reserve area of Kenya in the late 1960s by British geologist Campbell Bridges. It was introduced to the market through Tiffany & Co. in 1974, which positioned it as a premium coloured stone with a clear identity distinct from emerald. Fifty years later, it has built a collector base that values it for properties that directly address the weaknesses of the stone it was often compared against.
Why gemmologists prefer it to emerald
Tsavorite shares emerald’s Mohs hardness of 7.5, but tsavorite lacks emerald’s characteristic fracturing and cleavage. Emerald is brittle along its length; tsavorite is generally more resistant in service. More significantly, tsavorite is essentially never treated. The commercial emerald supply is predominantly oiled or resin-filled; tsavorite requires no such enhancement because its clarity is naturally superior. A tsavorite described as untreated is simply describing the normal state of the stone. For buyers tired of dealing with emerald treatment levels, this simplicity is genuinely valuable.
Colour range and quality markers
The finest tsavorite shows a vivid, saturated green comparable to the finest Colombian emerald, sometimes described as forest green or medium-vivid green by GIA’s colour system. Saturation and tone matter more than hue subtlety: stones that are too pale read as light green without distinction; stones that are too dark lose the brilliance that garnet’s high RI provides. Refractive index of 1.740–1.760, higher than emerald’s 1.565–1.602, means that well-cut tsavorite has exceptional brilliance and fire that emerald, even untreated, cannot match.
Supply constraints and size scarcity
Fine tsavorite above two carats is genuinely rare. The primary deposits in Kenya (Tsavo area) and Tanzania produce material that is predominantly small, under one carat. Stones above three carats with fine colour are exceptional and sell at exponentially higher per-carat prices than smaller stones of equivalent quality. This size scarcity is a real supply constraint, not a marketing construct, and means the price-per-carat curve for tsavorite is steeper than for most coloured stones.
Price guidance
Fine tsavorite of one carat with vivid green sells at $500–2,000 per carat wholesale. Two-carat stones of equivalent quality command $1,500–5,000 per carat. Three carats or above with fine colour has sold at $5,000–15,000 per carat. Stones below half a carat are commercially available at $100–500 per carat and are often used in melee settings. For investment purposes, sizes above two carats with documented fine colour and a major laboratory report are the appropriate target.