A razor strop is a flexible strip of leather or canvas used to straighten and polish the blade of a straight razor, a knife, or a woodworking tool like a chisel. Unlike honing or sharpening a blade, in which a whetstone removes metal bent out of alignment from the blade's edge, stropping the blade re-aligns the indentations without removing any material.
The strop may be a hanging strop or a hand-held paddle. Various abrasive compounds may be applied to the strop to aid in polishing the blade while stropping to obtain a mirror-like finish. The properties of the compound applied will alter the polishing result. Jeweler's rouge is a very fine abrasive compound. The green Chromium(III) oxide compound is most often used as an abrasive compound. Sprays containing diamond particles are another option.
Stropping is primarily done with straight razors, used for shaving, as these are the thinnest blades in everyday use, and require stropping at each use, due to the thinness of the blade. Kitchen knives are instead straightened on a honing steel, which is coarser. Any blade may in principle be stropped to polish it.
Two points are key to stropping: