The tools are described in chronological order of use; in this way, starting with the rough stone, we can follow the various stages which lead to the finished result.
It is important to note that the stone cutter may leave out certain stages, or stop before the end of the full process, according to the desired aesthetic effect, or the specific use of a particular stone.
The pictures show the tool on the stone block. The particular trace it leaves on the stone gradually appears, which often eradicates the marks left by the previous tool.
The tools used today are selected according to their efficiency (the cutting edges are often made from tungsten carbide, which wears out much more slowly than forged steel). Finishing tools are used to create a surface resembling that of ancient stone, enabling the new stones to blend in almost perfectly with the old ones.
Many tools have disappeared over the centuries, and only the marks they left on the stones remain. Essential restoration work results in many of these older stones being replaced with modern ones, and consequently these ancient marks are rapidly vanishing.
Clément Kelheter, the Oeuvre Notre-Dame's master sculptor, believes he has re-discovered an ancient tool, which has left its marks all over the cathedral, and has completely disappeared from today's toolbox. It is known as la toothed polka, derived from the hand adze used by carpenters, which is usually reserved for working on soft stones such as limestone. The marks it leaves behind are currently reproduced by the toothed hammer.
