Kyanite is a blue to cyan aluminosilicate which forms in triclinic bladed crystals. The mineral often forms in elongated, flat blades with strong color banding that runs parallel along the length of the crystals. It is found mainly in metamorphic rocks which formed during high pressure alteration of clay minerals during the formation of sedimentary rocks.

Kyanite has an unusual variable hardness which varies from around 5 Mohs along the parallel of the crystal’s length and 6.5-7 Mohs on its perpendicular axis. Due to its highly heat resistant properties, Kyanite has various industrial uses, such as high strength porcelain and many products which require a high heat resistance.

Kyanite’s name is derived from the Greek word ‘kyanos’, which means ‘deep blue’. Kyanos is also the origin of the color ‘cyan’. The highest quality Kyanite rough generally comes from Nepal but significant deposits have also been found in many locations around the world including Brazil, Burma, India, Myanmar and the United States.

Kyanite is still relatively rare in the gem world and considered to be somewhat exotic. Kyanite is very difficult to cut because of its variable hardness and cleavage, and requires an experienced lapidary worker to achieve the best results. The most popular kyanite gemstones have a vibrant sapphire-blue color with few to no inclusions. “Green Kyanite” is also sought after, but is a bit of a misnomer as it is actually more of a cyan-indigo color.