Is it brass or is it bronze ?                                                   

  The copper alloys comprise four main families of brasses: copper-tin-zinc alloys (red, semi-red and yellow brasses): "manganese bronze" alloys (high strength yellow brasses); leaded "manganese bronze" alloys ( leaded high strength yellow brasses); and copper-zink-silicon alloys ( silicon brasses and bronzes.) Ingot for remelting for the manufacture of castings molded in foundry's like Barr Casting Inc. may vary slightly from the ranges shown.
   
    Bronzes- Broadly speaking, bronzes are copper alloys in which the major alloying element is not zinc or nickel. Originally "bronze" described alloys with tin, are the only principal alloying element.  Today the term is generally used not by itself but with a modifying adjective. For wrought al-loys, (workabal) there are four main families of bronzes: copper-tin-lead-phos-phorus alloys (leaded phosphor bronze); copper-aluminum alloys (aluminum bronzes); and copper-silicon alloys (silicon bronzes).

   
    The cast alloys have four main families of bronzes; copper-tin-lead alloys (leaded and high leaded tin bronzes)  copper-tin-nickel alloys (nickel-tin bronzes) and copper-aluminum alloys (aluminum bronzes).

    The family of alloys known as "man-ganese bronzes", in which zinc is the major alloying element, is included in the brasses, above.
    Copper-Nickels --- These are alloys with nickel as the principal alloy element.

Source COPPER DEVELOPMENT ASSOCIATION INC.