Turn your jewelry into one-of-a-kind wonders with the rainbow agate 20mm coin beads. Agate is one of the oldest stones in recorded history. Agate includes numerous varieties of banded chalcedony. These coin beads are the perfect way to add color to designs. Showcase them in necklaces and bracelets. Gemstone beads are the perfect way to add natural beauty to your jewelry designs. Since gemstones are formed naturally, each bead is a unique treasure. These gorgeous gemstone beads are available by the strand, so you'll have plenty to work with.