Blister pearls are actually pearls imbedded into the oyster shell. Since mother of pearl comes from the ocean, some believe that it carries the power of that ocean. A nurturing stone, mother of pearl is said to relieve stress, calm the nerves, sooth the soul, and relax the body. It is thought to bring harmony to relationships, improve intuition, protect from negative energy, and even bring prosperity. The fresh water pearl is usually given for the first wedding anniversary, but some sources say that mother of pearl can also be given as a celebration of the first year of marriage. Mother of pearl is associated with the Zodiac signs of Gemini and Cancer.