Below is a list of Bronze manufacturers from Petaluma, California. Bronze is one of the most popular of copper alloys, in close competition with brass as the most commonly used alloy of this non-ferrous metal. The exact amount of copper in bronze is extremely variable and rangers from 60% to nearly 90% in some commercial grades. The second most prevalent element in bronze is tin, which is also variable commonly composing between 12% and 40% of the alloy.