A whetstone is a crucial tool for anyone looking to keep a blade sharp—but how long will it take for your whetstone to concave from use? Introducing the second most crucial tool for sharpening buffs: the 6” Truing Stone from EdgeLogix. Made of coarse silicone carbide with deep diagonal grooves, use the truing stone to flatten out your sharpening stone’s surface and aid in the sharpening process. Suitable for coarse and fine grits, maintain (or fix) your whetstone’s level surface and extend its life exponentially.