EARTHMOTHER SILVER NURSING CUPS FOR BREASTFEEDING - NATURAL HEALING FOR CRACKED OR SORE NIPPLES. Silver nursing Cups work to prevent sore nipples and protect and heal cracked nipples while breastfeeding. They are recommended by midwives and lactation consultants in antenatal classes, maternity hospitals and homes across Ireland. Earthmother nursing cups are made with 925 grade silver and can help prevent, protect and heal cracked or sore nipples, usually within 24 hours.