Linked Data Explorer
Deep mining methods, conglomerate mine of the Calumet and Hecla Consolidated Copper Co
This paper deals principally with the retreating method of mining as applied in the Calumet & Hecla Consolidated Copper [Companies] deep Conglomerate mine, pointing out some of the difficulties encountered in deep mining describing the particular methods used at Calumet to carry on a large-scale operation at great depth wiht a minimum hazard factor. The circular is one of a series dealing with mining methods and costs which is being prepared for and published by the United States Bureau of Mines.
- "This paper deals principally with the retreating method of mining as applied in the Calumet & Hecla Consolidated Copper [Companies] deep Conglomerate mine, pointing out some of the difficulties encountered in deep mining describing the particular methods used at Calumet to carry on a large-scale operation at great depth wiht a minimum hazard factor. The circular is one of a series dealing with mining methods and costs which is being prepared for and published by the United States Bureau of Mines."@en
- "Deep mining methods, conglomerate mine of the Calumet and Hecla Consolidated Copper Co"@en
- "Deep mining methods, Conglomerate mine of Calumet and Hecla Consolidated Copper Co"