Modern dimes rely on a cupronickel clad sandwich structure introduced by the Coinage Act of 1965. The outer face layers consist of 75% copper and 25% nickel, while the interior core is pure copper. Factoring in both the outer cladding and the inner substrate, the total alloy balance equals 91.67% copper and 8.33% nickel. This combination replicates the electrical conductivity of historic silver strikes, allowing legacy currency acceptors to validate the coin electronically.
Running a thumb along the perimeter reveals another critical dimension: the reeded edge details. The perimeter contains exactly 118 distinct vertical ridges, known as reeds. In early American history, reed indentations prevented fraudsters from shaving precious metal off silver and gold edges. Today, those 118 reeds provide tactile identification for visually impaired handlers and provide mechanical grip for automated sorting carousels.
