Silver Sheen Obsidian — Mexico

A polished oval cabochon of Mexican obsidian, measuring approximately 44 × 29 × 6 mm. As the stone turns beneath direct light, a soft silver sheen moves across its dark surface, at times resembling moonlight.

Obsidian is a naturally occurring volcanic glass formed when lava cools rapidly with minimal crystal growth. It is technically a mineraloid rather than a true mineral because its structure is not crystalline. Flow-aligned gas bubbles and internal layers can interact with light to create the shifting sheen seen in this piece.

View it beneath a lamp or use a smartphone light, slowly changing the angle to reveal its different expressions. Its compact, thin profile makes it easy to keep on a desk or in a drawer, though care should be taken to protect this brittle natural glass from impact.