Mother-of-pearl shells have been treasured as jewelry for many centuries and became highly sought in the 1850s. The continual movement of water in that time caused oysters to be washed and turned regularly on seabeds, consequently growing to immense sizes. These mother-of-pearl masses became used extensively in Europe for buttons, knife handles and jewelry. In China, mother of pearl has been prescribed for thousands of years to treat heart palpitations, dizziness and high blood pressure. In Vietnam, it has been powdered and taken orally to improve vision and remove cataracts. Mystics believe it to stimulate intuition, sensitivity, imagination and adaptability, and help with clarity in decision-making. Mother of pearl symbolizes faith, charity and innocence, and traditionally has been used to strengthen the environment and bring greater purity to the atmosphere.