Ionizing radiation on gemstones

Ionizing radiation can be used to alter the color of gemstones: it can produce fully saturated color in short times. The radiation causes changes within the gemstone's atomic structure that can result in a change in the way the stone absorbs and reflects light, leading to a change in its color. This process is known as "irradiation," and the gemstones that undergo this treatment are referred to as "irradiated gems." The process is commonly used on diamonds, emeralds, and other precious gems to enhance or improve their color. Topaz is the most commonly treated stone: typically it is yellow-orange and after radiation exposure it becomes blue. Diamonds and other precious gems may also be treated with radiation. Diamonds are usually irradiated to become yellow, blue-green or green, while pearls to become gray or black.

It is important to note that this process may affect the stability and durability of the gemstone, and it is also regulated by various international bodies to ensure that treated gemstones are properly labeled and disclosed to consumers. Despite this practice is not accepted worldwide, irradiated gemstones are internationally traded and are for sale, even in those states in which the practice is prohibited.