Smoky quartz crystals. Quartz is a form of silica (silicon dioxide) characterized by its hexagonal (six-fold) crystal symmetry. It is the second most abundant mineral in the Earth's crust after feldspar. It is colourless and transparent when pure but ranges from blue to pink in colour owing to a variety of natural chemical impurities | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Clutson, Michael |
Taille de l’image : | 5138 px × 3425 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |