Opal is an amorphous hydrated silicon oxide, chemical formula Si02.nH20. It is precipitated from silica-bearing waters in voids and fissures of certain rocks. Water molecules trapped in the silica framework account for the milky lustre and brilliant pastel colours that make opal such a desirable precious stone. Specimen is from Opal Butte, Oregon, USA and actual width is 75 mm. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wiersma, Dirk |
Bildgröße: | 5616 px × 3744 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |