Gold-Filled Faceted Prehnite Necklace, 17" Wipe Clean Gently With Soft Dry Cloth after each use. Do not wash in solubles. Wipe Clean Gently With Soft Dry Cloth After Each Use. Do not wash in solubles. Gemstones may have been treated to improve their appearance or durability and may require special care. The natural properties and composition of mined gemstones define the unique beauty of each piece. The image may show slight differences to the actual stone in color and texture