| Brass is an alloy of copper and
zinc. Some types of brass are called bronzes,
despite their high zinc content.
Brass is a valuable manufacturing material because of its hardness and workability. Alpha brasses, with less than 40% zinc, are
malleable and can be worked cold. Beta
brasses, with a higher zinc content, can only be worked hot, but are harder and stronger. White brass, with more than 45% zinc, is too
brittle for general use. Some types of brass have other metals added to modify their properties.
Brass has been known to man since prehistoric times, long before zinc itself was discovered. It was produced by melting copper
together with calamine, a zinc ore. During this process, the zinc is extracted from
the calamine and instantly mixes with the copper. Pure zinc, on the other hand, is too reactive to be produced by ancient
metalworking techniques.
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