Mother of Pearl 6x13mm Black Bevel Edged Rectangle Bead - 15-16 Inch Black Tiger Teeth which is not Jasper but

which is not Jasper but rather a combination of Feldspar and Quartz

an opaque silicon dioxide mineral and form of microcrystalline Chalcedony

Plated to prevent oxidization

which can be yellow

and turquoise is a leftover mineral from these practices

Mother of Pearl 6x13mm Black Bevel Edged Rectangle Bead - 15-16 Inch Black Tiger Teeth which is not Jasper butMother of Pearl, also known as Nacre, is an iridescent composite of organic and inorganic material most known for being the coating of pearls. It is produced by certain molluscs as an inner shell layer, and forms around pieces of sand or other irritations within such a molluscs shell to create pearls. Mother of Pearl is white with an iridescent sheen.