Every year, the Wickenburg Chamber of Commerce sponsors a festival to celebrate the town's mining and ranching heritage, and participants get to shovel and pan for gold!
The stability of drilling chamber is an important facet to ensure the safe operation of VCR mining method.
凿岩峒室的稳定性是VCR采矿法安全的重要保障。
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The paper describes the sequence of mineral products used by the Chinese, mining pit and chamber, mining method and the source of the term "mineral resources".