Grandidierite is one of the rarest gemstones a collector can ever hope to own. First described from Madagascar in 1902 and named after explorer Alfred Grandidier, facet-grade material remained virtually unobtainable for a century until small finds near Tranomaro (Madagascar) reached the market. Even today, clean faceted stones are measured worldwide in hundreds of carats per year, not tons.Its color is unmistakable: a serene bluish green to greenish blue, with strong trichroism that shifts between blue, green and near-colorless as the stone turns. Hardness of 7.5 makes it perfectly wearable — a true rarity that doesn’t have to live in a display case.GEMIC Institute maintains one of the more substantial grandidierite selections available online: natural stones, each tested and certified by our accredited gemologists in Siem Reap, each shown in real photos and video. Every specimen is one of a kind. Worldwide tracked shipping and a 30-day return policy apply. Serious collectors seeking investment-grade grandidierite can contact us for first access to new finds.