Transparency

Optical Properties

Definition

The degree to which light passes through a gemstone, described on a scale from transparent (clear) to translucent (partly allowing light through) to opaque (blocking light).

Detailed Explanation

A transparent gem allows objects to be seen distinctly through it, as with fine sapphire or aquamarine. Translucent stones allow light to pass but diffuse it, obscuring images — moonstone and rose quartz fall into this category. Opaque gems like malachite, turquoise, and lapis lazuli transmit no light. Transparency is influenced by the presence of inclusions, fractures, and the inherent crystal structure of the material.

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