Opal’s shifting play of kaleidoscopic colors is unlike any other gem. Writers have compared opals to volcanoes, galaxies and fireworks. Admirers gave extraordinary opals poetic names like Pandora, Light of the World and Empress. Opals reveal the glory of the gemstone kingdom; in them you find the passionate fire of ruby, the royal purple of amethyst, the brilliant blue of sapphire and the vivacious green of emerald, all at once creating the most enthralling play of colors imaginable. Opal is an October birthstone, along with tourmaline.