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 (database) Gemstone (database) GemStone/S is computer software, an application framework that was first available for the programming language Smalltalk as an object database. It is proprietary commercial software. GemStone Systems was founded on March 1, 1982 as Servio Logic, to build a database machine based on a set theory model. Ian Huang instigated the founding, as the technology adviser to the CEO of Sampoerna Holdings (Putera Sampoerna), by recruiting Frank Bouton (President) who was the cofounder of Floating Point Systems Inc, Dr. Michael Mulder (Vice President of Engineering) who was the Group Manager for Advanced Processor Design at Sperry Univac and