Cut agates. Assortment of cut and polished agates. Agate is a variety of quartz (silicon oxide). The colours are produced by impurities in the mineral. The concentric bands are formed as successive layers of quartz precipitate out of solution during the formation of the agate | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Molloy, Cordelia |
Taille de l’image : | 3650 px × 4936 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |