placer mining

基本解释

This primitive form of placer mining is still used in some places for panning gold.
這種原始的砂鑛開採形式至今還在一些地方用來淘金。
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Mechanized placer mining, with special devices for washing and separating waste from valuable minerals, is used in productive alluvial deposits.
機械化砂鑛開採用於含鑛量豐富的砂鑛牀．利用專門設備來淘洗、分離廢物與有用鑛物。
In conducting coastal open air placer mining or shore-based well drilling to exploit seabed mineral resources, effective measures must be taken to prevent pollution to the marine environment.
露天開採海濱砂鑛和從岸上打井開採海底鑛産資源，必須採取有傚措施，防止汙染海洋環境。

Dines likes, among others, mining concerns Placer Dome (nyse: PDG - news - people ) and Hecla Mines (nyse: HL - news - people ).
FORBES: Magazine Article
Placer Dome has joined Rio Tinto and three other mining houses to form the World Alliance for Community Health.
ECONOMIST: Companies and health