Opalite (a synthetic glass, often confused with Opal)

Hardness: 5.5-6.5 (Mohs); Color: Bluish-white with an opalescent sheen, often showing orange or amber flashes when backlit; Luster: Vitreous to sub-vitreous; Crystal structure: Amorphous (lacks crystalline structure as it's glass); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Opalite is a man-made glass, typically composed of glass with trace amounts of metal (like neodymium) to give it its characteristic color and optical effects. Natural opal forms from solutions of silica and water that seep into cracks and voids in rocks. As water slowly evaporates, it leaves behind a silica gel that hardens over millions of years.

Predominantly used in costume jewelry, ornaments, and decorative items due to its attractive play of color and affordability. It is often carved into beads, cabochons, and small sculptures.

While visually similar to natural opal, Opalite is not a gemstone in the traditional sense; it is a type of glass. It is often created to imitate more expensive natural opals and moonstones. The 'play-of-color' in Opalite is due to light scattering within the glass, whereas in natural opal, it is caused by the diffraction of light by microscopic spheres of silica.

To identify Opalite in the field (or distinguish it from natural opal), note its often uniform, milky blue appearance with a specific warm glow when light passes through it. Natural opal can have a much more varied and vibrant play of color, and often exhibits internal imperfections or a potch (common opal) base. Opalite typically feels warmer to the touch than natural stone. Common locations: As a synthetic material, it is manufactured worldwide, not found organically in geological formations.