2.15 CT Natural Grandidierite Rare Gemstone from Madagascar

A rather rare mineral, lovely blue-green grandidierite is seldom seen in gem or jewelry collections. Translucent material is sometimes cut into cabochons. Faceted pieces are very rare, but recent discoveries of transparent material may bring more to the market.

Grandidierite has a hardness of 7.5, which makes it very resistant to scratching and ideal for jewelry use. However, it also has perfect and good cleavage in two directions, which makes it challenging to cut. Of course, its scarcity has also made this a relatively little known gemstone.

Since its initial discovery, samples of grandidierite have been found in only a few locations around the world, including Malawi, Namibia and Sri Lanka. But the few gem quality specimens have come mainly from Madagascar.

Grandidierites display strong trichroic pleochroism. That means they can show three different colors depending on the viewing angle: dark blue-green, colorless (sometimes very light yellow), or dark green.

Grandidierite is considered one of the rarest and most expensive gemstones in existence. It can fetch prices up to $20,000 per carat.

Since grandidierite is so rare, we took several specimens to GIA in Bangkok for verification. GIA confirmed the samples as natural untreated grandidierite and they issued special reports (GIA Notable Letters) on several of the gems. The gems are described as "extremely rare" with "very high transparency," with grandidierite characterized as "one of the rarest gemstones on Earth."
1908-24