Brass make brass was not recognised as a metal. The King James Bible makes many references to "brass". The Shakespearean English form of the word 'brass' can mean any bronze alloy, or copper, rather than the strict modern definition of brass. The earliest brasses may have been natural alloys made by smelting zinc-rich copper ores. By the Roman period brass was being deliberately produced from metallic copper and zinc minerals using the cementation process, and variations on this method continued until the mid-19th century. It was eventually replaced by speltering, the direct alloying of copper and zinc metal which was introduced
Industrial metal were initially influenced by the Earache roster (namely Godflesh, Napalm Death and Bolt Thrower). The German band Oomph! after their second album Sperm started to play industrial metal combined with elements of death metal and groove metal until the album Plastik. Sepultura singer Max Cavalera's Nailbomb, a collaboration with Alex Newport, also practiced a combination of extreme metal and industrial production techniques. A lesser-known example of industrial death metal is Meathook Seed, made up of members of Napalm Death and the Florida death metal group Obituary. An industrial music fan, Obituary guitarist Trevor Peres suggested drum machines for "The End