The stone comes from the Saurat Valley in Ariège in the Pyrenees, where it has been quarried since the 14th century – today, processed by only one remaining company. Known as “Grey Gold” (French: Or Gris), this schistous sandstone mainly consists of silicon (58%), alumina (9%), and lime (13%). As is typical with natural stones, the grain size can only be roughly estimated at 900 #, as it depends on the quarry conditions and the age of the stone.
The stone is suitable for sharpening and honing, both dry and slightly moistened, and delivers an excellent, fine sharpness. The back of the leather strap is equipped with nubuck cowhide for deburring.