Kyanite

Kyanite is one of those stones that has a little mystery to it. Its name comes from the Greek word "kyanos" meaning blue — and that cool, clear blue is its signature color, though it also occurs in white, grey, green and even nearly black. What makes Kyanite genuinely unusual is that it has two different hardness ratings depending on which direction you cut it — 4.5 along the crystal and 6.5 across it. It forms under high pressure during the metamorphism of sedimentary rocks, and the elongated crystal structure gives each bead a distinctive natural character. There's also a beautiful old legend that Kyanite suspended from a human hair will follow the earth's magnetic force and travelers once used it as a compass.