Types of Sharpening Stones

Sharpening stones are also called honing stones and whetstones.

Diamond Stones

Sharpening stones keep knife blades sharp.Sharpening stones keep knife blades sharp.
The word "whet" means to sharpen a blade, and is not a reference to water. Sharpening stones are either natural or man-made stones. Sharpening stones often need a lubricant, either water or honing oil, depending on the type of stone. Some stones need regular "flattening," a process of flattening a concave groove that develops in the stone through repeated use. The size of sharpening stones can vary from a pocket stone to a bench stone. No one stone will be perfect for all uses, and some individuals keep several types of stones on hand.

Diamond stones are made by bonding industrial diamond powder or pieces to plastic or steel. They cut quickly, are long-lasting and use water for lubrication. Diamond stones do not need flattening. Coarse-grit diamond stones are used to flatten water stones and oil stones.

Hard Ceramic Stones

Hard ceramic stones are made from a hard aggregate of aluminum oxide. They are durable and considered “lifetime” stones if cared for properly. These stones use water for lubrication, but can be used dry. India stone is an example of a hard ceramic stone.

Oil Stones

Oil stones are fine grades of whetstones that use honing oil for lubrication. They are commonly in bench form, and most of them come from sedimentary, microcrystalline quartz, called novaculite. Oil stones are durable and need only occasional flattening. Stones of this type include Arkansas, Ouachita or Washita stones from Arkansas. Oil stones that are very fine grade are called polishing stones. Oil stones can be messy to use.

Water Stones

Water stones are traditional Japanese sharpening stones mined from sedimentary deposits. Water is the only lubricant that can be used on a water stone because oil can ruin a water stone. These stones are soft and sharpen easily, but they wear more quickly than other stones as they continuously break down, leaving new sharpening surfaces. Water stones must be flattened as they wear. Most of the quality, natural water stone supply is depleted, and remaining stones are costly. Man-made water stones made of abrasive particles (grit) bonded to resin or ceramic are readily available and less expensive. The abrasive particles of man-made stones are father apart than on oil stones, making them resistant to clogging and glazing. Soak water stones in water for 15 minutes before use.

About the Author

Annette Strauch has been a writer for more than 30 years. She has been a radio news journalist and announcer, movie reviewer for Family Movie Reviews Online, chiropractic assistant and medical writer. Strauch holds a Master of Arts in speech/broadcast journalism from Bob Jones University, where she also served on the faculty of the radio/TV department.