In non zinc containing dental amalgam alloy, the percentage of zinc present is

The ANSI/ADA specification also includes a notation about the presence of zinc in amalgam alloys, with more than 0.01% zinc classified as zinc containing and those with less than 0.01% as non-zinc alloys. Zinc has been included in amalgam alloys as an aid in manufacturing; it helps produce clean, sound castings of the ingots used for producing lathe-cut alloys. The presence of contamination within the amalgam must be avoided because it can degrade the integrity of the restoration.