For molding from sulfur
Sulfur is made beautiful by mixing in soot black or powdered sanguine, which makes it harder and stronger. After letting it melt entirely until it becomes liquid and similar to oil, then mixing it with verdigris, you can use it for casting a lizard or something else in plaster, very cleanly.
at left top margin of folio 012r
You must not cast it until it has cooled down and lost all its bubbles and eyes, and its surface has fallen and become flat as water. Soot black gives it a fine luster and makes it neater. Use yellow sulfur of the best kind, as the greyish natural sulfur is no good. Don’t cast it in the wind and cold for it would fill with bubbles.