A whetstone is a tool used for sharpening blades, such as knives and chisels. It is typically made from materials like natural stone or synthetic compounds. Whetstones come in various grits, which indicate their coarseness; lower grits are used for repairing damaged edges, while higher grits refine the edge for a sharper finish. To use a whetstone, the blade is usually lubricated with water or oil, depending on the type of stone. The blade is then drawn across the surface at a specific angle, allowing the stone to grind away material and create a sharper edge. Proper maintenance of a whetstone can enhance its effectiveness and longevity.