Brass is a copper-zinc alloy containing approximately 70% Copper and 30% Zinc by mass, and one of the most versatile and widely produced alloys in modern industry. Its combination of moderate strength, excellent corrosion resistance, good machinability, and attractive golden appearance makes it the default material for plumbing fittings, musical instruments, decorative hardware, and a fair few mechanical components. Its most relevant application within The Oceanykan Federation is in the manufacturing of Brass-cased Cartridge: brass's ductility allows it to expand under pressure and seal a gun's chamber, then spring back sufficiently to allow extraction, a property no cheaper material reliably replicates. Because Oceanykans consume so much ammunition throughout the year, brass recycling has emerged as a parallel industry, allowing brass smelters to save up on a portion of the raw materials necessary to produce new material.
