In this Chapter the following expressions have the meaning hereby assigned to them:

a) Copper-zinc base alloys (brasses)

Alloys of copper and zinc, with or without other elements. When other elements are present:

(i) zinc predominates by weight over each of such other elements;

(ii) any nickel content by weight is less than 5%. [see copper-nickel-zinc alloys (nickel silvers)]; and
(iii) any tin content by weight is less than 3%. [see copper-tin alloys (bronzes)].

(b) Copper-tin base alloys (bronzes)

Alloys of copper and tin, with or without other elements. When other elements are present, tin predominates by weight over each of such other elements, except that when the tin content is 3% or more the zinc content by weight may exceed that of tin but must be less than 10%.

(c) Copper-nickel-zinc base alloys (nickel silvers)

Alloys of copper, nickel and zinc, with or without other elements. The nickel content is 5 per cent or more by weight [see copper-zinc alloys (brasses)].

(d)Copper-nickel base alloys.

Alloys of copper and nickel, with or without other elements but in any case containing by weight not more than 1% of zinc. When other elements are present, nickel predominates by weight over each of such other elements.