Boulder opal formation. Boulder or nodular opal in a sandstone matrix from Queensland,Australia. Opals are not truly crystalline and are therefore mineraloids. They consist of hydrated silica glass | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Natural History Museum, London |
Taille de l’image : | 3684 px × 4744 px |
Model Release : | Non requis |
Restrictions : | - |