History of Brass

Ancient metalworkers in the area now known as Syria or eastern Turkey knew how to melt copper with tin to make a metal called bronze as early as 3000 B.C. Sometimes they also made brass without knowing it, because tin and zinc ore deposits are sometimes found together, and the two materials have similar colors and properties.
By about 20 B.C.-A.D. 20, metalworkers around the Mediterranean Sea were able to distinguish zinc ores from those containing tin and began blending zinc with copper to make brass coins and other items. Most of the zinc was derived by heating a mineral known as calamine, which contains various zinc compounds. Starting in about 300 A.D., the brass metalworking industry flourished in what is now Germany and The Netherlands.
Although these early metalworkers could recognize the difference between zinc ore and tin ore, they still didn't understand that zinc was a metal. It wasn't until 1746 that a German scientist named Andreas Sigismund Marggraf (1709-1782) identified zinc and determined its properties. The process for combining metallic copper and zinc to make brass was patented in England in 1781.
The first metal cartridge casings for firearms were introduced in 1852. Although several different metals were tried, brass was the most successful because of it's ability to expand and seal the breech under pressure when the cartridge was first fired, then contract immediately to allow the empty cartridge casing to be extracted from the firearm. This property led to the development of rapid-fire automatic weapons.
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