Blue Kyanite 10mm Round - 15-16 Inch R1851 It is transparent or translucent

It is transparent or translucent

The color of Smoky Quartz is due to natural irradiation and traces of aluminum within the crystal lattice of the stone

any color of the rainbow

Obsidian is produced when lava erupts from a volcano and cools rapidly with minimal crystal growth

Blue Kyanite 10mm Round - 15-16 Inch R1851 It is transparent or translucentKyanite often occurs as long, bladed, striated crystals, transparent or translucent with a pearly luster. An aluminum silicate mineral, it may appear in white, pink, yellow, orange, green, blue, gray and black. In addition to its value as a gemstone, Kyanite is also extremely useful in industrial applications due to its high heat resistance. It is often used in kiln furniture and foundry molds, as well as for brake shoes, grinding wheels and cutting