Many French horns, for example, are made of nickel silver, an alloy of copper, zinc, and nickel (it's silver in name and color only), and some are made of nickel bronze, an alloy of copper, tin, and nickel. (Brass itself is an alloy of copper and zinc.) Many brass instruments are silver-plated (sterling silver on brass), and some are gold-plated.

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Exactly what that copper content is is debatable: various sites give brass or bronze as the alloy and with different copper contents.

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In the materials group, Reliance Steel, one of the largest U.S. metals service centers, distributes a line of more than 100, 000 metal products, including carbon, alloy, stainless and specialty steel, aluminum, brass as well as copper products.

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