Give your designs edgy style with the Dakota Stones sardonyx 7x12mm faceted nugget beads. Available in 8-inch strands, these beads feature black color striped with bands of white. These beads feature a rock-like nugget shape created from cut facets. Sardonyx is an onyx that is characterized by parallel lines of sard and different colored minerals. It is a distinct and dramatically banded variety of chalcedony composed of quartz layers. Sardonyx is believed to improve memory and increase one's analytical talents. Sardonyx is mined all over the globe and is also known as tuxedo agate. Use these trendy beads with dark metallics, like gunmetal.