Multi Strand Black Freshwater Pearl Necklace and Silver Clasp Back to black! This wonderful triple strand necklace is made of 7-8 mm freshwater cultured pearls. Each pearl is individually knotted on a silk string for safety. The clasp is in 925 sterling silver. The length is adjustable. Pearl features: Pearl size: 7 to 8 mm Shape: button Color: black Luster: excellent Pearl type: freshwater cultured Necklace features: Length: 17 in - 43 cm Knotting: between each pearl Clasp: 925/1000 sterling silver claw Being genuine freshwater pearls, the color is black with hints of oil (blue, green, gold, purple and brown).