Zircon
What is Zircon?
Zircon is a mineral belonging to the group of nesosilicates. It’s primarily found in Australia, Thailand, and Sri Lanka. Zircon is often used as a gemstone and is popular for its high refractive index and range of colors, including colorless, yellow, red, and blue.
Zircon is a versatile gemstone that comes in a variety of colors, often including colorless, yellow, red, and blue. Its high refractive index gives it exceptional brilliance, making it a popular choice for jewelry such as rings and pendants.
| Chemical Classification | Inorganic - Zirconium silicate |
| Color | Comes in a variety of colors, including blue, red, yellow, green, and clear. Blue is the most popular. |
| Streak | White |
| Luster | Vitreous to adamantine. |
| Transparency | Typically transparent, but can be opaque in some varieties. |
| Occurrence | Australia, Sri Lanka, and Cambodia. |
| Formation | Zircon crystals form in igneous rocks and have been found in sedimentary deposits. |
| Diaphaneity | Transparent |
| Cleavage | Perfect in two directions |
| Mohs Hardness | 6.5 - 7.5. |
| Specific Gravity | Approximately 3.93 - 4.73, but can vary based on type and treatment. |
| Diagnostic Properties | High refractive index, often heat treated. |
| Chemical Composition | ZrSiO4 |
| Pleochroism | Weak to strong, depending on the color of the Zircon. |
| Crystal System | Tetragonal |
| Optical Properties | Uniaxial (+) |
| Refractive Index | 1.810 - 2.024 |
| Birefringence | 0.059 |
| 2V angle | Measured: 78° to 82° |
| Dispersion | 0.039, which is very high and contributes to Zircon's fire. |