[4] In the early 1930s, Morris Ashby in Britain had licensed the New Jersey zamak alloy.
In 1933, National Smelting licensed the refluxer patent with the intent of using it to produce 99.99% zinc in their plant at Avonmouth.
Over time it retains its strength and hardness better than the other alloys; however, it becomes more brittle, shrinks, and is less elastic.
It has the same composition as zamak 2, except with more magnesium in order to produce finer grains and reduce the orange peel effect.
In order to reduce inter-granular corrosion a small amount of nickel is added and impurities are more strictly controlled.
[2] Common uses for zamak alloys include appliances, bathroom fixtures, die cast toys and automotive industry.
[35][36] In World War 2, zamak alloy buttplates were one of three variations common on Canadian and American-made .303 Lee Enfield rifles, particularly during mid-war production.