A whetstone is a tool used for sharpening blades, such as knives and scissors. It is typically made from materials like ceramic, diamond, or natural stone. Whetstones come in various grits, which indicate their coarseness; lower grit numbers are used for repairing damaged edges, while higher numbers refine the edge for a sharper finish. To use a whetstone, the blade is usually moistened 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 technique ensures effective sharpening and prolongs the life of the blade.