Put drops of gleaming black shine in your designs with the onyx 4mm round beads from Dakota Stones. Available in 8-inch strands, these small round beads feature a glossy black color that would look beautiful in between larger, more colorful beads. Onyx is a variety of chalcedony that is similar to agate, with straight rather than curved bands. Nearly all black onyx on the market has been rendered a uniform, permanent black color with a treatment by sugar and acid or heat. This process has been used on onyx for thousands of years and does not decrease the value of the stone. Mined in Brazil, India and Madagascar, onyx is said to enhance steadfastness and determination while setting one's mind to a task. Dakota Stones offers gemstones that are all useable in jewelry designs because every bead is checked to ensure they are cut and drilled correctly, that the finish is right and that the beads look distinct to their stone type.