Damascus

Damascus is the generic term for two different types of steel (or sometimes steel and another metal) forged together in a special process. The process involves folding the two steels several times and then etching it to bring out the pattern created by the folding. The bladesteel in the C01 Worker from the Evolution edition of workers is a damascus steel made by Tim Zowada.

In his own words:

I made the steel for the Evolution edition. The steel was sent to Japan for blanking, grinding and heat treating. The steel was a lamination of W2 and ASTM203E.

For the Mule team and bone/Ti Delicas, Spyderco utilized a VG-10 core with Damascus outer layer:

Spyderco’s Damascus is a laminated fifteen-layer steel with a Suminagashi pattern. The Damascus steel is composed of layers of erosive and non-erosive material over a VG-10 core center. The erosive layers are hard martensite stainless steel and the non-erosive layers are anti-corrosion nonferrous metal. These layers block carbon particles in the core from spreading to the outer layers. After layering the blade is forged to intentionally distort the layer-lines making a complicated, artistically beautiful pattern called Suminagashi. Suminagashi is the traditional Japanese art form of creating ripples of Chinese ink on the surface of water. This steel mimics the art form with interesting results on a knife blade. Once the layers are distorted, the blade is bathed in acid etching the pattern to vivid relief.