Tanaka Ironwood Tanaka Knives come with iron wood handles. These are all handmade, custom knives that are hot-forged with 32-layer damascus blades. The core blade is made from SG-2 (R-2) Powdered Steel (HRC 62 and up). Superior in Sharpness and Durability. The handles are hand crafted from iron wood and are attached to the knives with decorative inlaid mosaic rivets.