Yttrium aluminium garnet (Ce:YAG) is used as a phosphor in cathode ray tubes and white light-emitting diodes, and as a scintillator. YAG for a period was used in jewelry as a diamond and other gemstone simulant. Colored variants and their doping elements include: green (chromium), blue (cobalt), red (manganese), yellow (titanium), purple (neodymium), pink, and orange. As faceted gems they are valued (as synthetics) for their clarity, durability, high refractive index and dispersion. The critical angle of YAG is 33 degrees. YAG cuts like natural garnet, with polishing being performed with alumina or diamond (50,000 or 100,000 grit) on common polishing laps. YAG
Green Is the Colour song was a regular part of the band's shows from early 1969 through 1970, then less common in 1971. It was played for the last time during their short tour of Japan and Australia in August 1971. The song was later played by Nick Mason's Saucerful of Secrets. with: Green Is the Colour "Green Is the Colour" is a track on Pink Floyd's 1969 "More". It was composed and written by Roger Waters and sung by David Gilmour. A tin whistle is heard in the song, played by drummer Nick Mason's then-wife Lindy. A live version of the song was