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2 years ago

Research the compositions of Pennies. What was the composition of each of your Pennies prior to treatment

Chemistry

1 answer:

LenKa [72]2 years ago

7 0

Answer:

History of composition

Years Material Weight (grains)

1944–1946 gilding metal (95% copper, 5% zinc) 48 grains

1947–1962 bronze (95% copper, 5% tin and zinc) 48 grains

1962 – September 1982 gilding metal (95% copper, 5% zinc) 48 grains

October 1982 – present copper-plated zinc (97.5% zinc, 2.5% copper) 38.6 grains

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