The blue Belgian chunk - grit 6000
Sharpen like the pros!
The first written mention of the mining of Belgian boulders dates back to 1625. The Roman scholar Pliny (23-79 AD) already mentioned the special whetstones from the Ardennes in his writings. To this day, this deposit is unique in the world due to its natural composition.
The finest garnets (5-20 microns) are embedded in veins of 5-20 cm in the approximately 480 million year old slate sedimentary rock of volcanic ash and clays. Garnet follows diamond, corundum and beryl in terms of hardness. Similar to a soccer, its surface is divided into facets (rhombic dodecahedron). It is precisely these characteristics, the hardness and roundness of the garnet particles, that lead to these outstanding sharpness properties.