Any punk can get a digital scale, these days. A bill weighs a gram, a nickel weighs five grams. A post-1982 penny weighs 2.5 grams. Tare the scale, and go to work. Anyone challenges the weight, demonstrate with coins. A nickel and a penny is a quarter ounce....a penny and a bill is close to an eighth ounce.
Now that’s a typical blue eye answer. You don’t like the weight? My AK says it right on.