Material:Natural Black Shell Pearl Strand length:7.5inch 8mm:Aound 20 Bead Per Strand 10mm:Aound 24 Bead Per Strand 12mm:Aound 16 Bead Per Strand Shape:Round Shape Faceted Cut Hold size :1.0mm Wide Usage: beads are excellent for Beading,Jewerlry Making,Jewelry Design,DIY gifts,Arts & Craft,Necklaces,Bracelets,Yoga Bracelets,Earrings,Ring,Home & Wedding Decoration Guaranteed 100% natural Black Shell Pearl not treated in any way...Being AAA grade,each and every bead on these strands has strong brilliant A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite) in minute crystalline form, which has deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other shapes, known as baroque pearls, can occur. The finest quality of natural pearls have been highly valued as gemstones and objects of beauty for many centuries. Because of this, pearl has become a metaphor for something rare, fine, admirable and valuable. We take the pictures under professional studio lights and enlarge the item.The goal is to show the natural beauty of gemstone.Depending on your PC monitor screen,the colors of the stones may be slightly different than the pictures.