Why do the crystals inside geodes vary in color?
Crystals inside geodes will vary in color for a number of reasons. The solutions inside a vug may consist of varying concentrations of different mineral solutions. The mineral crystals that form from these solutions may have a specific color associated with them, such as malachite (green), azurite (blue) or rhodoschrosite (pinkish-red). Minerals that normally have a clear crystalline structure may appear clear or be colored by small amounts of impurities such as iron. In other cases, the minerals inside a vug may be exposed to varying amounts of radiation which can affect their color.
