Without question, this vivid red, gemmy, octahedron of spinel on white calcite, is a world class competition thumbnail. Most Mogok spinels are simply loose singles, off matrix. This one, carefully excavated from a miniature at Bill Larson's lab by Irv, is unrepaired and remains on matrix due to the careful prep work. You almost never see this quality of crystal, aside from the additional aesthetics of it being on matrix! The well formed, complete crystal measures .8 cm across. It is truly a thing of beauty.