Grandidierites are one of the world’s rarest gems. Although, they are found in abundance in mines, gem-quality grandidierite is extremely rare. These gems are found mostly in Madagascar. Their color ranges from a strong bluish green to greenish blue due to the presence of trace amounts of iron. On the Mohs scale of mineral hardness, grandidierites measure 7.5-8. These gemstones feature strong trichroic pleochroism, meaning that the gemstone shows three different colors depending on the viewing angle – dark blue green, colorless, or dark green