Brass is an alloy of copper and zinc. The proportions of zinc and copper can be varied to create a range of brasses with varying properties. For jewelry, the most commonly used percentages of copper and zinc is 67% and 33%. This mixture helps the brass become stronger and more durable than copper alone, which allows for superb electroplating quality, and thus, it is the perfect combination for fashion jewelry.
Black coating uses either ruthenium or TIN cobalt black to give a piece of jewelry a light black or completely black appearance. It is very durable and resistant to scratches. Black plating gives the jewelry piece a sense of masculinity and high-tech.