Coloured scanning electron micrograph (SEM) of an uncut sapphire. Sapphire is a typically blue gemstone variety of the mineral corundum (aluminium oxide). Sapphire is very dense and very hard. Non-gem quality sapphire is often used as an industrial abrasive, or as scratch-resistant glass. Magnification: x150 when shortest axis printed at 25 millimetres. | |
Licence : | Libre de droits |
Crédit: | Science Photo Library / DENNIS KUNKEL MICROSCOPY |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |