Topaz gemstones. This silicate mineral (aluminium silicate fluoride hydroxide) can range in colour from golden brown to yellow. A blue variety is often confused with aquamarine,although it does not occur in nature. Topaz can be polished in a variety of shapes: oval (upper left),cushion cut (centre right) and opposed bar (centre) are seen. It is rated as 8 out of 10 on the Mohs hardness scale,with diamond rated as 10 | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Lawry, Lawrence |
Bildgröße: | 4155 px × 3393 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |