TOPAZ GEMSTONE
Topaz makes an ideal gem. A good hardness and desirable colors, combined with a relative abundance and availability makes it one the most popular gemstones. The most valuable colors of Topaz are the golden orange-yellow type, called Imperial Topaz, and the dark pinkish-red and orange-red colors. Value increases with a deepness of color in orange and reddish hues. The most commonly used colors of Topaz in jewelry are the blue types. It was not until this past century that blue Topaz became widespread on the gem market, since virtually all blue gem Topaz is irradiated and heat treated.
Chemical
| Chemical Formula | Al2SiO4(F,OH)2 |
| Color | White, Colorless, Blue, Red, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Multicolored |
| Hardness | 8 |
| Crystal System | Orthorhombic |
| Refractive Index | 1.610 – 1.638 |
| SG | 3.4 – 3.6 |
| Transparency | Transparent |
| Double Refraction | .014 |
| Luster | Vitreous |
| Cleavage | 1,3 – basal |
| Mineral Class | Topaz |
Topaz – The November Birthstone
Topaz is the original modern birthstone for the month of November. Its position as a birthstone contributes to the gem’s popularity. Topaz jewelry can be found for sale in almost every jewelry store.
In 1952, Jewelers of America made a few modifications to the list of modern birthstones. That was when citrine, a yellow to orange to reddish brown variety of quartz, was added as a second birthstone for the month of November.