Opal is the national gemstone of Australia, the continent where Granite Transformations began in 1996. Opal is appreciated for its ability to diffract light. Metropolis Opal uses hand-cut Karma glass, assembled in a repetitive, irregular pattern. The Metropolis Opal mosaic is characterized by incorporating different-sized tiles of the same or contrasting shades, or even different tones. Our installers can use two options: pre-mounted on TREND PLUS or with a clear plastic film on the face, depending on the area where they are assembled.