The heavy slabs are cut across the grain into set sizes which are a little larger than the finished face size, using a saw that dates to 1929, when electricity first came to the mine. The material is so hard, that a blade lasts only 200 hours of cutting.
The remaining processes are all carried out by hand, in the same way that they have been performed for centuries.
Docking the slate is the original process of dividing the large, sawn pieces (clogs) to a thickness of four slates (about 32mm) ready to be rived. This cutting is achieved with the use of a small chisel and a 21 pound mallet, cutting with the grain.

Once docked, the slate can be rived - splitting the sections, again by hand, with mallet and broad bladed chisel into four slices each of the finished thickness for use.