101 - Another Black Enamel
Have 6 lbs of the enamel base material described above [chapter 93]. Now take 2 oz of prepared zaffer, 2 oz of crocus martis made with vinegar [chapter 17], and 2 oz of Spanish ferretto. Grind these three powders well, blend, and mix them thoroughly with the above said base material.
Inflame this mixture in a furnace
crucible glazed as usual. When it has fused and clarified , throw it into water, and then return it to the crucible, where it will purify quickly. Watch to see if the color develops to your liking, remove it, and form it into cakes as usual. If you clarify the glass weil, and incorporate the color well, this will be a beautiful black enamel for goldsmiths.