PLACER GOLD MINING METHOD, PLACER GOLD MINING BOAT USED IN THIS METHOD, PLACER GOLD DIGGING AND SEPARATING METHOD AND SYSTEM THEREFOR, AND PLACER GOLD SEPARATING METHOD AND SYSTEMTHEREFOR

摘要

A placer gold separating method comprising subjecting placer gold- and goldore-containing sand and gravel layers accumulated on the bottom of the waterof a river and placer gold- and gold ore-containing sand and gravel layersformed deep in the ground to excavation or suction excavation by utilizing awater pressure difference, causing a mixture of the excavated or suctionexcavated placer gold- and gold ore-containing sand, gravel and water to flowhorizontally by the action of a pressure fluid, and separating the placer goldand gold ores by utilizing a specific gravity difference while the mixture isflowing; and a system for this method. A placer gold mining boat used topractice this method and provided thereon with a combination of a suctionexcavation means, a mixture transfer means, a means for separating placer goldby utilizing a specific gravity difference, and a means for discarding theremaining mixture from which the placer gold has been separated. A placer goldseparating method characterized by causing a mixture of placer gold and goldores or pulverized gold ores and water to flow in a metallic cylinder,generating a magnetic field by a magnetic field generating means provided onan outer circumferential surface of the metallic cylinder, and magneticallydepositing the placer gold in the mixture on the inner surface of the metalliccylinder, whereby the placer gold is separated.