Native gold crystals. This soft,heavy,acid- resistant metal is usually found in quartz veins,as a natural alloy with silver,and in concentrations of sedimentary origin. The main gold-bearing districts are Witwatersrand (South Africa),the Mother Lode (California,USA),the Yukon (Alaska,USA),Porcupine (Northwest Territory,Canada) and the USSR. It is used as a monetary standard,in jewellery,in dentistry and for scientific and electronic instruments | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Fisher, Arnold |
Bildgröße: | 4399 px × 4063 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |