Calsilica (also called Rainbow Calsilica) is not a naturally occuring stone but, rather a man-made synthetic stone manufactured from a mixture of calcite and resin. The different colored bands swirling around in calsilica beads are actually powdered rock that is colored and stabilized with resin. Calsilica is a fun, fashion-forward way to get the look of gemstones in your jewelry designs without a big price tag. Want to see some coordinating calsilica pendants to begin planning your next necklace design? Check them out here! Learn more in our gemstone glossary.