Based on results of the electrochemical polarization and salt fog tests, high manganese brass
(C99700) is the most corrosion-resistant alloy and high strength yellow brass (C86300) and aluminum bronze (C95400) are the least resistant to corrosion.
The pure copper core makes up half of the metal in the coin, with the two layers of manganese brass
each taking up one-fourth of the thickness.
The new coin, manganese brass
over a copper core, is not intended to replace the paper bill, 6 billion of which are printed each year.
The new alloy is a three-layer "clad" system of manganese brass