Mercury gold panning extraction. Close-up of a gold prospector pouring mercury from a small tube into a pan which contains flour gold mixed with water and soil. Panning involves swirling gravel from a stream or river in water in a shallow dish. The lighter stones and rocks will be lost,while the heavier metal ores,such as gold and silver,will be left behind. With fine rock fragments,as with this 'flour' gold,chemical extraction is needed. Photographed by Russell Lee (1903-1986) in May to June 1940,in Pinos Altos,New Mexico,USA | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Library of Congress |
Bildgröße: | 3624 px × 2437 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |