About Opal Stone Chemistry: SiO2nH2O Hydrated silica with impurities. Hardness: 5.5-5.6 Color:White, Black,Blue, multicolored . Chakra: Varies according to color. Meanings: Creativity, spontaneity, relationships,memory, happy dreams and changes. Opal stone is  very unique in the gems kingdom. In Roman times, opal was sit next to...