Grandidierite is a rare mineral that was first discovered in 1902 in southern Madagascar.

The mineral was named in honor of French explorer Alfred Grandidier (1836–1912) who studied the natural history of Madagascar.

While trichroism can usually help distinguish grandidierites from other gems, lazulites can occur with blue-green colors and show colorless/blue/dark blue pleochroism.

Large transparent faceted grandidierite specimens are extremely rare.

The largest cut specimen currently known to the GIA weighs in at 763.5 carats.