Agate. Agate is an aggregate of different forms of silica (SiO2) that have formed concentric bands within a geode. A geode forms when the silica precipitates from liquid onto the inside surface of an empty pocket in a host rock. Specimen from Tierra del Fuego,Argentina,measuring approximately 6 x 10 centimetres | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Natural History Museum, London |
Taille de l’image : | 3129 px × 2792 px |
Model Release : | Non requis |
Restrictions : | - |