If you have been around the cutlery world long enough you probably remember when white ceramic sharpening rods were marketed under the trade name “Moon Stone.” Coors Ceramic (yes, that same Coors from Colorado) originally developed a new type of aluminum oxide ceramic for use in the space program. More or less by accident, it was also discovered that the material made a great fine-grit abrasive for sharpening edged tools. For reasons I don’t fully understand, Coors once warned me that they would rather not have the general public associate them with the sharpening products. As a result, you very seldom hear their name mentioned in connection with ceramic hones.
Aluminum oxide, in both in its natural corundum form and synthetic varieties, has major advantages over the various quartz/silica-based sharpeners, such as Arkansas stones and most natural Japanese waterstones. At 9 on the Mohs scale of mineral hardness, it is far harder than a stone from the quartz family (Mohs 7) which, in turn, makes it much better suited to sharpening modern high-alloy steels.
In man-made form, it is very consistent in quality and relatively inexpensive. Ceramics can produce extremely fine-grit sharpeners that are ideal for finishing and polishing edges that have first been honed on some type of coarser product. I personally feel a ceramic rod is vastly superior to the traditional all-metal “butcher’s steel” for regular use at a cutting work station. A butcher’s steel only straightens an edge, but a ceramic hone will also remove just enough metal to create a new cutting surface. As long as you don’t let the knife get too dull, a ceramic rod works equally well for touching up hunting, fishing, pocket and butchering knives as you go.