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Bronze, or bronze-like alloys and mixtures, were used for coins over a longer period. Bronze was especially suitable for use in boat and ship fittings prior to the wide employment of stainless steel owing to its combination of toughness and resistance to salt water corrosion. Bronze is still commonly used in ship propellers and submerged bearings.
A bronze is an alloy of copper and other metals, most often tin, but also aluminium and silicon. Aluminium bronzes are alloys of copper and aluminium. The content of aluminium ranges mostly between 5% and 11%.
Bell bronze is a two-phase alloy, meaning some of the tin is not dissolved in the copper grains but exists between them. This makes the metal harder and more brittle than a single-phase alloy, and also affects the way the metal responds to hardening by hammering and lathing, and greatly restricts the use of mechanised techniques of manufacture.
Brass is more malleable than bronze or zinc. The relatively low melting point of brass (900 to 940 °C; 1,650 to 1,720 °F, depending on composition) and its flow characteristics make it a relatively easy material to cast. By varying the proportions of copper and zinc, the properties of the brass can be changed, allowing hard and soft brasses.
Mohs hardness kit, containing one specimen of each mineral on the ten-point hardness scale. The Mohs scale (/ m oʊ z / MOHZ) of mineral hardness is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of minerals through the ability of harder material to scratch softer material.
On the other hand, the bronze article indicates that "bronze" is a general term for copper alloys, and therefore includes brass: brass, a subset of the bronze alloys in which zinc is the principal additive I am not qualified to judge which of these is correct, but they seem to contradict each other. Similar comment posted on Talk:Bronze.
Gold, silver and bronze or copper were the principal coinage metals of the ancient world, the medieval period and into the late modern period when the diversity of coinage metals increased. Coins are often made from more than one metal, either using alloys, coatings ( cladding / plating ) or bimetallic configurations.