Britannia silver has a fineness of 11 troy ounces , 10 pennyweights , or about 95.833 % silver , .
Sterling silver has a fineness of 11 troy ounces .
Britannia silver has a fineness of 11 troy ounces , 10 pennyweights , or about 95.833 % silver , whereas sterling silver has a fineness of 11 troy ounces .