MORE TIPS FROM THE BOOK OF FORMULAS

Heat evenly around the area to be cut, then place in water. The sudden cooling will crack it around the heated area.

 

Soak plaster of paris in a solution of alum, bake it in an oven, then grind into a powder. Then mix with water, stir in a colour pigment to give the veins and clouding effect. It will dry very hard, and can be highly polished.