How to Identify Bronze vs. Brass

Many of us have wondered how to tell bronze from brass, and which is the optimum composition of metals for marine use.  You’ll want to read the Cruisers Forum thread, “Identifying Bronze versus Brass.” Posts cover information ranging from cast products to screws, nuts and bolts. The posts are definitive and include a couple from very knowledgeable people.  You’ll pick up some real world experience such as you should always go with red brass (gunmetal), which is 85-5-5-5 composition, or 85 percent copper, 5 percent tin, 5 percent lead and 5 percent zinc.  Avoid yellow brass in marine applications. The following is from a mechanical engineer with extensive experience in corrosion engineering:  the metallurgical standards for marine bronze in the US are stricter than in Europe.  Therefore “If you replace sea cocks in Europe, plan to do it again in a couple of years. I find this one really dangerous.”