Natural Grandidierite 5.32ct Cushion Cut

A cushion with a great deal going on inside it. The underlying body color is a medium teal-green, but it is nowhere near uniform: broad chartreuse and olive-yellow zones run down the left side and across the top shoulder, while a dark, nearly opaque zone anchors the right edge and the lower right corner. Between the two the stone opens into clearer blue-green windows where light passes straight through, and a scatter of fine dark crystal points sits across the middle. The overall effect reads more like a landscape than a single flat color.

Madagascar is the main commercial source for grandidierite and produces it across the full range from pale mint to deep blue-green. The species is also strongly trichroic, showing a different color along each of its three crystal directions, which is part of why the hue can look so different from one facet to the next on a single stone. Untreated. At 7 to 7.5 on the Mohs scale it takes a good polish and wears well, and at 11.9x9.1mm this is a substantial face-up size for a species that rarely gets cut this large.

Natural grandidierite, Madagascar, sold loose.