placer deposits

См. также в других словарях:

• Placer mining — (pronounced plass er ) refers to the mining of alluvial deposits for minerals. This may be done by open pit (also called open cast mining) or by various forms of tunneling into ancient riverbeds. Excavation may be accomplished using water… …   Wikipedia

• placer mining — ☆ placer mining [plas′ər ] n. mining of placer deposits by washing, dredging, or other hydraulic methods * * * Oldest method of recovering gold from alluvial deposits. It takes advantage of gold s high density, which causes it to sink more… …   Universalium

• placer mining — ☆ placer mining [plas′ər ] n. mining of placer deposits by washing, dredging, or other hydraulic methods …   English World dictionary

• placer deposit — Natural concentration of heavy minerals caused by the effect of gravity on moving particles. When heavy, stable minerals are freed from their matrix by weathering processes, they are slowly washed downslope into streams that quickly winnow the… …   Universalium

• Placer deposit — In geology, a placer deposit or placer is an accumulation of valuable minerals formed by deposition of dense mineral phases in a trap site. The name is from the Spanish word placer , meaning alluvial sand . Types of placer deposits include… …   Wikipedia

• placer — noun /ˈpleɪsə/ a) Someone who places or arranges something. Placer gold comes from the weathering of the primary veins releasing the gold to be transported by water action and concentrated in gravel or sand beds. b) Someone who deals in stolen… …   Wiktionary

• Placer County, California — Coordinates: 39°04′N 120°44′W / 39.06°N 120.73°W / 39.06; 120.73 …   Wikipedia

• placer — I. noun Date: 1579 one that places: as a. one that deposits or arranges b. one of the winners in a competition II. noun Usage: often attributive Etymology: Spanish, from Catalan, submarine plain, from plaza place, from Latin platea broad street… …   New Collegiate Dictionary

• placer — placer1 noun 1》 a person who places something. 2》 a person or animal gaining a specified place. 3》 Brit. informal a dealer in stolen goods. placer2 noun [often as modifier] a deposit of sand or gravel in the bed of a river or lake, containing… …   English new terms dictionary

• placer claim — A mining claim located on the public domain for the purpose of placer mining, that is, ground within the defined boundaries which contains mineral in its earth, sand, or gravel; ground which includes valuable deposits not in place, that is, not… …   Black's law dictionary

• placer — /pleysar/ In mining law, a superficial deposit of sand, gravel, or disintegrated rock, carrying one or more of the precious metals, along the course or under the bed of a watercourse, ancient or current, or along the shore of the sea. Under the… …   Black's law dictionary