Sterling Silver Claddaugh Hoop Earrings Sterling Silver Claddaugh Hoop Earrings Millimeter Measurement Comparisons In Words to remember every 25MM equals 1-inch and 12.5MM equals 1/2-inch Dime=17MM,Penny= 19MM,Nickel= 21MM,Quarter= 24MM For international orders customers are responsible for all custom fees.