Pure silver is entirely hypoallergenic, but is often too soft to use in jewellery. This is why sterling silver is popular for jewelry, as it contains 7.5% of other alloys. Sterling silver uses copper, another hypoallergenic metal, as its alloy. With both metals combining, sterling silver 925 is perfect for earrings and rings.Hypoallergenic refers to any product that should not trigger an allergic reaction.