These natural beads are made using dried lava. They are then electroplated to take on this beautiful metallic finish! Lava is a form of molten rock that originates from volcano eruptions. We offer these fun beads a large variety of sizes. Although they are considered to be a form of stone, they are fairly lightweight making them great for jewelry. Each bead measures approximately 4 x 4mm with a hole size of approximately 1mm. You will receive a full strand measuring approximately 15".