In honing tools, the wire edge produced from grinding is removed and the cutting edge is polished. While doing this on the water soaked Blue Whetstones something unusual happens. When the cutting edge is drawn across the smooth surface of the stone the fine crystals of garnet are released with particles of stone to produce, in combination with the water a very fine slurry. The garnet crystals cut lightly into the metal taking very fine shavings. The hardness of the garnet allows for a very quick removal of metal, but the roundness allows for a very exact polish of the honed edge. This combination of speed and fineness is world-wide unique. The „Blue Whetstone“ creates a finely honed edge with which makes it is easy to cut through wood fibres.

This is the traditional whetstone that contains 35 to 40 % of garnets which gives it the best grinding characteristics. Because of the odd nature of the environment the Coticule is found in the thinner layers, because of that it needs some work; the gluing and shaping.

 

This Coticule is sorted according to visual characteristics and sold as Selected and Standard in rectangular and odd shaped ( = bout).

This standardization only takes in account how the Coticule is shaped and does not effect the excellent grinding characteristics. “Selected” provides a homogeneous stone while “Standard” shows cosmetic defects or natural colourisation.

The rectangled Coticule:

The odd shaped Coticule (= bout):

Coticule formstones: for whetting round and V-shaped chisels.

Slipstone: this whetstone is very suitable for whetting round chisels. Each Coticule slipstone has 1 curve and a fixed diameter: either less than 7 mm, between 7 and 12 mm or more than 12 mm. The length is on average 75 mm, the width is available with various diameters.

Multiform: this Coticule is very suitable to whet V-chisels and round chisels. The slipstone part does not go from big to small (Unlike the BBW version) and has 1 fixed diameter. Various sizes are available: a width of less than 5 mm is thin, more than 5 mm is big.  A length of less than 50 mm is small, more than 50 mm is large.

The Coticule slipstone:

The Coticule multiform:

In 1996/97 working together with the laboratories from the University in Ličge, we had the geological deposits of rock close to the traditional „Yellow Whetstone“ closely analysed. With amazing results. We discovered a high quality whetstone with identical sharpening properties as the „Yellow Whetstone“ but only blue in colour, which derives from deposits of iron oxide. Almost 30 % of it’s weight is garnet, as opposed to the yellow which has approx. 35-40 % garnet, this means it works just a little slower.

The thickness of the Belgian Blue Whetstone is between 13 and 16 mm and unlike the Coticule, the BBW is a single side stone. It has a grit of ca. 4000 and contains 20 to 30 % garnets which allow the stone to whet at a fast speed. The colour of the BBW is blue-grey.

The cotcarb is, like the Coticule, a double side stone. It consists of a BBW top side and a Carburandum (synthetic stone) bottom side. The BBW has ca. 4000 grit and the Carburandum layer has 600 grit. The Carburandum side is used to do the hard work of preparing blunt knives, the BBW top layer will do the real sharpening.

The Cotcarb “Kitchen” has a handy wooden grip, very convenient to whet all sorts of knives in the kitchen.

The Cotcarb kitchen: