Rainbow gems were brilliant treasures that were not actually gems, but silicon-based lifeforms native to the planet Gallinore. They matured only after thousands of years, and the glow they produced was caused by their inner light. Despite their biologic nature, rainbow gems could be used as lightsaber crystals. Tenel Ka Djo, the Princess of Hapes, had a tiara of rainbow gems worth the price of an entire solar system. She used some of the crystals in her second lightsaber, after her first one malfunctioned and led to the loss of her arm.