8.1" Polished Peach Moonstone Tower - Madagascar
This is a chatoyant piece of peach moonstone (potassium aluminum silicate feldspar) that has been shaped and polished into an obelisk/tower. The base is cut flat so that it displays nicely on a hard surface.
Moonstone is a quite common and well known gemstone that earned its name from its white to bluish "glowing" appearance under light. Good quality moonstone will have a deep light/color play under light that is similar to chatoyance, however in moonstone it is known as adularescence. This light play is a result of albite crystals within the orthoclase feldspar crystal lattice that form as a scale-like crystal formation. The light then reflects and scatters off of these formations, resulting in what appears to be a glow from beneath the surface of the stone.