Common brass is also called rivet brass after it's most common use -- making rivets. It is considered the standard brass, composed of 37 percent zinc. It is worked cold.
Called prince's metal, alpha brass consists of less than 35 percent zinc. It is often worked cold because it is ductile at room temperature, and can be forged, rolled or pressed. Gilding metal is an alpha brass, with only 5 percent zinc. This is the softest brass, and is only used in ammunition. The brass used for jewelry is 15 percent zinc and therefore also an alpha brass. It is called rich low brass. Low brass is 20 percent zinc. It is easily drawn into wire, and is used to make hoses that are metal but still flexible. Another alpha brass is cartridge brass. It is 30 percent zinc and is often drawn into long bars or tubes to work. It's most common use is to make cartridges for guns.
Alpha-beta brass has two stages, an alpha phase where it is like alpha brasses, and a harder, stronger beta phase. The zinc content is between 35 percent and 45 percent with the rest of the metal being copper. This brass is also called duplex brass, or hot-working brass, because it can be worked at higher temperatures than alpha brass.
Common brass is an alpha-beta brass.
Beta brass is 45 percent to 50 percent zinc. It is worked while hot and is good for casting. It is harder and stronger than duplex brass. Beta brass is not used often, and the two main designations of brass are alpha and alpha-beta. After adding more than 50 percent zinc, brass becomes too brittle to work with. This is called white brass.
Tin is added to brass alloys to improve corrosion resistance. This allows brass to be used underwater. Admiralty brass is copper with 30 percent zinc and 1 percent tin and is used in marine metalwork. For saltwater applications, it has been replaced with aluminum-alloyed brass , but admiralty brass is still used in freshwater projects. Naval brass is similar, with 40 percent zinc and 1 percent tin, and is used in saltwater brass work.