An alloy of copper and zinc. It used to be made by melting copper in contact with the zinc carbonate, calamine (ZnCO3), under charcoal in a crucible. Early brasses contained 70-90% copper and 10-30% zinc. The colour of brass changes with increasing zinc content from a rich copper-red through to pale yellow to white as the zinc increases. Gilding metal containing 10-15% zinc is suitable for cold working. It is used for ornamental work and jewellery. Red brass contains 30% zinc and 70% copper and has good working properties. The common form of brass is 60% copper, 40% zinc and is known as yellow brass or Muntz metal. In Europe from about 1750 it was made by melting the two metals together (Direct process).