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
Gemstone Healer place after the events of "Gemstone Warrior". In the first game, the player had to recover the Gemstone, a relic of incredible power forged by the gods and focusing the natural magic of the world. This, they entrusted to Man alone and for a time, there was great prosperity and peace. But the Demons, led by Nicodemius, had managed to boil to the surface and take the Gemstone. Unable to destroy it, Nicodemius fragments it into five pieces that they hide in their vast lair. By going into the Netherworld, the protagonist is assumed to have succeeded in this quest