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 Publishing Suspenstories" Vol. 1 and "Tales From the Crypt" Vol. 1 have been published. In early 2009, the future of Gemstone Publishing was unclear, after reports of unpaid printing bills, particularly from the EC Archives. In April, Geppi responded to the uncertainty, noting that while there had been "a reduction in staff at Gemstone," such moves did "not [signal] the end of Gemstone Publishing." Seven months after Geppi's optimistic statements, the last batch of Gemstone's Disney comics appeared in November 2008, complete with previews for next month's issues that Gemstone was to fail publishing. BOOM! Kids acquired all comic publishing licenses