308F - Spyderco's Golden Stone sharpening device is all curves and angles for sharpening any edge. U.S.A. Made, from Alumina Ceramic, it's created through a process combining a bonding agent with alumina particles (that are actually synthetic sapphires 15 to 25 microns in size). It is then kiln fired at temperatures exceeding 3000 degrees F (1649-C) where it reaches 9 (out of 10) on a Mohs hardness scale and is cooled in stages.
Ceramic sharpeners are used dry without oil or water. The fine grit Golden Stone is closed-cell and won't wear with usage or time, excelling at polishing and professionally finishing any edge. Holding the stone vertically on a tabletop and tilting it from one side to the other creates a 20° angle (40° total angle) for sharpening knife blades. Both sides are elliptical for sharpening PlainEdges, and SpyderEdges (serrations). Positioned on its' side horizontally creates a 12.5° angle for sharpening scissors. Suede leather carry case doubles as a non-skid counter top pad for tabletop sharpening.