Cents have went through composition changes through the years, but no silver. The various compositions have weight variances. I’ll list the list below. This cent isn’t a little heavy. I think the variance is +\- .13 grams, but a copper expert will soon correct that if it’s wrong. Are you certain your scale is accurate? Even if it is a little heavy I don’t think that is enough out of tolerance to be worth a premium, but others may correct that.
Bronze Lincoln Cents
Dates: 1909-1942, 1947-1962, 2009 Composition: 95% copper, 5% tin and zinc Weight: 3.11 grams Diameter: 19 mm
Zinc Coated Steel Lincoln Cents
Date: 1943 Composition: steel coated with zinc Weight: 2.70 grams Diameter: 19 mm
Copper Lincoln Cents
Dates: 1944-1946, 1962-1982 Composition: 95% copper, 5% zinc Weight: 3.11 grams Diameter: 19 mm