Brass Hello readers, it’s time for metallurgy class again, this time focusing on brass. Brass is the second most common metal we handle at Progressive Bronze, and it’s offered as an alternative to bronze for nearly everything we make. Where as bronze is an alloy of copper and most often tin, brass is an alloy of copper and zinc. It popped up some time after bronze, in the first millennium BC. Its composition was not well understood for more than 2000 years, as zinc in metalli