Iolite is the gem variety of the mineral Cordierite. It describes the transparent to translucent form of Cordierite, and it has recently become a popular gemstone. Iolite can be light to deep blue, and usually has a purplish tinge to it. Deeper colored stones are more valuable. Iolite is very affordable and durable, and can be used as a substitute for more expensive blue gemstones such as Sapphire. It is named from the Greek "violet", alluding to the purplish tinge often exhibited by this gemstone.
| Chemical Formula | Mg2Al4Si5O18 |
| Color | Blue, Purple, Gray |
| Hardness | 7Â -Â 7.5 |
| Crystal System | Orthorhombic |
| Refractive Index | 1.55Â -Â 1.62 |
| SG | 2.6Â -Â 2.7 |
| Transparency | Transparent to translucent |
| Double Refraction | -0.01 |
| Luster | Vitreous |
| Cleavage | 3,1 |
| Mineral Class | Cordierite |
No comments:
Post a Comment