Gem-quality kyanite crystals are pale to deep blue, or white, grey, or green. Colour distribution in crystals may be uneven, with darker blue patches towards the interior.
Kyanite is found in metamorphic gneiss and schist, and in pegmatite veins through metamorphic rocks. It may be weathered out into alluvial deposits. Gem-quality crystals are found in Burma, Brazil, Kenya, and the European Alps. Alluvial deposits are found in India, Australia, and Kenya, and in several localities in United States.
Kyanite crystals have two hardness values: they are softer parallel towards the direction of cleavage, and harder perpendicular into it.