The art of glass shewing how to make all sorts of glass, crystal and enamel : likewise the making of pearls, precious stones, china and looking-glasses : to which is added, the method of painting on glass and enameling : also how to extract the colours from minerals, metals, herbs and flowers ... : illustrated with proper sculptures / written originally in French, by Mr. H. Blancourt, and now first translated into English ; with an appendix, containing exact instructions for making glass-eyes of all colours.

CHAP. CXIII. Another Way of making Paste for Precious Stones, with Saturnus Glorificatus.

THERE are some who use transparent Flints cal∣cined, to add to Saturnus Glorificatus, and make Paste for Artificial Gems; but as we esteem Natural Chrystal prepared much more proper for that Work, we should employ it before calcined Flints.

Take therefore of Natural Chrystal prepared ten Pounds, of Saturnus Glorificatus ten Pounds, the whole reduced to fine Powder, which mix well to∣gether; then put it in a Pot in a Glass-house Furnace, there to be melted and purified three Days: Then cast it into a great Wooden Vessel full of cold Wa∣ter, then dry it, and put it in the Furnace in the same Pot, the better to purifie. When this Chry∣stalline Matter is well melted, and clear, take out the Pot; and when it is cool, pound it to an impal∣pable Powder on a Marble, then keep it in a Glass Vessel well stopped, for fear of Dust falling in; and that Matter will serve for a Basis or Stuff to make all sorts of Artificial Gems of.

We need not here repeat the Way of making them of this Past, because we have shewn it before in seve∣ral others; but for sake of the Curious who are never weary of Learning, we will do it; besides that there

are some who may take pleasure in reading it, as we do in writing it; particularly we will treat of some Species of Stones we have, as yet, not at all men∣tioned.