Discovery and Naming of Grandidierite
Discovered by French naturalist explorer Alfred Grandidier in southern Madagascar in 1902, this rare gemstone was named in his honor. Grandidier extensively studied the natural history and geography of Madagascar, making multiple visits to the island.
Early Acquisition and Rarity of Grandidierite Stone
Initially, the crystals obtained were not of facet grade material but were highly sought after by gem collectors. Even samples of the rare gem were prized possessions.
New Deposit Discovery
After a century of limited production, a new deposit near the original locality of Andrahomana, outside the town of Tranomaro, was found. High facet grade material began entering the gem market in Bangkok, attracting the attention of dealers, especially after GIA issued certificates describing the gem crystal samples as Grandidierites.
Characteristics and Rarity
Grandidierite is considered one of the rarest gemstones globally, with a Mohs scale hardness of 7.5. Its chemical formula is close to Kornerupine. It comes in colors ranging from dark green to bluish-green and colorless. Fine cut gems can command prices ranging from $10,000 to $100,000 per carat.
Occurrence and Value
Crystals of up to 8 cm in length and limited amounts of gem grade rough are located in southern Madagascar. The gemstone is highly valued, with specimens fetching considerable prices in the market.
Grandidierite remains an extraordinary gemstone, sought after by collectors and enthusiasts alike, with its rarity and exceptional beauty continuing to captivate the gem market.