التعدين وتكرير النحاس - ets-power.asia. The extraction of copper from its ores and the preparation of copper metal or . mines indicates that the art of extracting the metal included some refining. .. the open-pit method is the most practical for the mining of large tonnages of material.
البريليوم محجر كسارة. Quarry - WikipediaA quarry is the same thing as an open-pit mine from which minerals are extracted. The only non-trivial difference between the two is that open-pit mines that produce building materials and dimension stone are commonly referred to as quarries.
