These natural beads are made using dried lava! 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. They look very earthy and our customers tell us they are great for oil infusions! Each bead measures approximately 5 x 6mm with a hole size of approximately 1mm. You will receive a full strand measuring approximately 16".