Kyanite Kyanite is named after the Greek word for "blue". Its color indeed can make it a lovely gem with a near sapphire-like blue. However kyanite also comes in colorless, white, gray, green or yellow. Color is often not consistent throughout the crystal, often showing white streaks in an medium blue. Kyanite is a layered crystal with a luster that is vitreous to almost pearly, which gives it an interesting and unique look. Its variable hardness is a significant characteristic that has to be taken in consideration by the gem-cutter. The hardness of kyanite is 4-4.5 (Mohs scale) when scratched parallel to the long axis of the crystal and 6-7 when cut perpendicular to or across the long axis. It's a very nice gemstone for earrings or pendants, cut in cabochon or facet cut. Set in silver or white gold, kyanite becomes a fine piece of jewelry. Kyanite is believed to aid self-expression, communication and supernatural abilities.