| Topaz
is a silicate mineral that is valued
as a gemstone.
Topaz
occurs in the colors Blue, Blue-Green,
Brown, Yellow and Pink. Red is extremely
rare. The colorless variety is most
abundant in Sri Lanka. Matale, Rattota
area, Balangoda region recently
discovered around Seegiriya. |
| Gemological
Information |
| Color
: |
Colorless,
Blue, Yellow-Brown, Pinkish Orange,
Red-Orange, Red-Brown, Tan. |
| Refractive
Index: |
1.629
- 1.637 |
| Chemical
Composition: |
AL(F,OH)2SIO4 |
| Hardness: |
8 |
| Density: |
3.52
- 3.56 |
| Crystal
Group: |
Orthorhombic |
| Ocurrence: |
Brazil,
Sri Lanka, Nigeria, Germany, Australia,
Japan, Russia, Australia, Ireland,
Zimbabwe. |
| Pure
topaz may be colourless and, when
brilliant-cut, has been mistaken
for diamond. It may also be coloured
various shades of yellow, blue,
or brown |
|
|
|