Moonstone is the name given to the member of a feldspar group of gemstones. They are remarkable for their chatoyancy or adularescence (Glow or inner light). Moonstone's body color can range from colorless to white, gray, brown, yellow, orange, green, or peach . But its beauty is in its sheen, which can be white to deep flame blue. The sheen effect is caused by the intergrowth of two different types of feldspar with different refractive indexes: These intergrowths result from compatible chemistries at high temperatures becoming incompatible at lower temperatures and thus a separating and layering of these two phases when the stone cools down during its genesis. The resulting shiller effect is caused by a ray of light entering a layer and being refracted back and forth by deeper layers before leaving the crystal. This refracted ray has a different character than the incident one and this produces the moonlike glow.

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