Citrine crystals. This mineral is a variety of quartz (silicon dioxide) that is used as a gemstone. Since it is rare in nature,it is often obtained by heat treatment of another variety of quartz,the purple amethyst mineral,to produce the cream colour seen. In nature,heat from molten rocks may produce citrines from amethysts | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Bond, Martin |
Bildgröße: | 4676 px × 3735 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |