Calamine brass a mixture of the virtually indistinguishable zinc ores smithsonite and hemimorphite) as the zinc component of brass. The resulting brasses, produced by heating a mixture of copper and calamine to a high temperature for several hours (allowing zinc vapor to distill from the ores and permeate the metallic copper), contained a significant amount of slag material resulting from the non-zinc components of calamine. The use of ore rather than metallic zinc also made it difficult to accurately produce the desired final proportion of copper to zinc. This process is known as cementation. Calamine brass was produced using proportions of two-sevenths
The Big Ore The Big Ore The Big Ore () is a 1964 drama film directed by Vasily Ordynsky and based on the novel by Georgi Vladimov. Viktor Pronin (Yevgeni Urbansky) returned from the army to the bride (Svetlana Zhgun), and she – the other. Then Victor went to "great" Kursk ore, where the work is in full swing – all live in anticipation of the first car of ore. To check Pronyakin, Brigadier (Vsevolod Sanaev) gives him beaten MAZ: mend – a long time came. The guy got in the "hostel" to repair the car and began to put one after the