YOUR SOURCE FOR COLOR

Zircon is a natural gemstone made of zirconium silicate (ZrSiO₄) that is admired for its strong sparkle and ability to bend light. This light-bending property, known as a high refractive index, gives zircon its impressive brilliance and colorful flashes called “fire.” Zircon also shows birefringence, meaning light splits into two rays as it passes through the crystal, sometimes making facet edges appear doubled. Although it is often confused with cubic zirconia, zircon is a naturally formed mineral, while cubic zirconia is a laboratory-made material with a completely different chemical structure.

From a scientific and gemological standpoint, zircon’s crystal structure can be altered over millions of years by tiny amounts of radioactive elements, such as uranium and thorium, trapped within the crystal. This process can partially damage the crystal lattice and affects how well the stone transmits light. Zircons are therefore described as high, intermediate, or low based on the condition of their structure. Heat treatment can repair some of this damage and change the stone’s color, which is why many blue zircons are heat-treated. With a hardness of about 6 to 7.5 on the Mohs scale and a relatively high density, zircon is both a durable jewelry gemstone and an important mineral for understanding Earth’s early geological history.