Quartz crystals. These are also known as rock crystals. Quartz (silicon dioxide) is colourless when pure,but the presence of impurities can give a range of colours including white,pink,yellow,blue,green and smoky brown. The colourless variety is highly prized by collectors. Quartz is one of the commonest minerals in the Earth's crust (12% by volume) | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / TH FOTO-WERBUNG |
Taille de l’image : | 4504 px × 3121 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |