Calamine brass Calamine brass Calamine brass is brass produced by a particular alloying technique using the zinc ore calamine directly, rather than first refining it to metallic zinc. Direct zinc smelting appears to have been unknown in Europe until the mid-18th century, even though the alloyed calamine brass was in use for centuries, and metallic zinc was produced directly via reducing-atmosphere smelting in India and China from the 12th century CE onwards. Brass is an alloy of copper and zinc and, when it was first developed, methods for producing metallic zinc were unknown. Metallurgists wishing to produce brass thus used calamine (actually
Group 12 element extremely high density of around 46 g·cm, over twice that of osmium, currently the most dense element known, at 22.61 g·cm; unhexquadium should be the second most dense element in the first 9 periods of the periodic table, with only its neighbour unhextrium (element 163) being more dense (at 47 g·cm). Metallic unhexquadium should be quite stable, as the 8s and 8p electrons are very deeply buried in the electron core and only the 7d electrons are available for bonding. Metallic unhexquadium should have a very large cohesive energy due to its covalent bonds, most probably resulting in a high