After this manner the Aq. Regis is killed, and every metal which it has yet retaineth, it dismisseth like a yellow powder, whether it be gold alone, or mixed with copper or iron, which powder is to be dried, and reduced after the manner which shall strait-way be taught.
N. B. That the water after the total precipitating of the metals, being exhaled in a Copper Kettle unto a thin skin, and exposed in peculiar vessels unto the cold, it will afford thee a beautifull Salt-peter, concreted or grown together into drops or Ice-acles, whereof thou may’st again make an Aq. fortis, to be again made use of for the like operations.
He that shall rightly operate shall get so much Salt Peter as will recompence the charges of the Aq. fortis, and Aq. Regis: So that he shall extract his gold without costs. For five or six pounds of Aq. fortis, wherein two or three pounds of Salt is dissolved, and the which hath at length been precipitated by a sharp Lixivium prepared with Calx-vive, doth render ten pound of Salt Peter, the which doth answer the price of five pound of Aq. fortis, and this is the manner of extracting gold out of minerals without cost.
XXXIV. Another and better manner of extracting gold by Aq. Regis.
Take of by torrifying made into ashes, pour the extraction into an iron Pot, and stir the Calx with an iron Spatula while it boileth. All the sharp spirits do stick fast to the the phlegm alone vanisheth by exhalation. When therefore the spirits are wholly con-centred with the and are dried, they are to be put into a close Tigil or Crucible upon Coals in a secret Crucible or melting Pot, then the fire expels the con-centred spirits into a receiving vessel; the which spirits may be used for a new extraction. A fugacious gold mixt with iron, remaineth with the which Calx being reduced in a Furnace fit for those operations, which the Germans do call Stichofen, draws out a lead mixt with gold, the which being expelled by a Cupel enricheth the operators with the best gold and silver.
N. B. But if such lead should not contain so much of gold and silver, as that it should deserve a separation by a Cupel, that is again to be mixt with and to be reduced into ashes, and the operation is so long to be repeated, untill the lead being rich enough in gold, may deserve that separation.
The separation is also to be perfected with the Bellows, lest so great a plenty of lead should be melted out of the Tests, which operation requires much fire, yet the lead may be collected or conjoyned in the Test without a wastefull melting, as shall be taught hereafter.
XXXV. An easie making or composing of Aq. Regis, for extracting of minerals.
Because a plenteous quantity of spirit of Salt is easily prepared, the Salt Peter is onely to be dissolved therein, and with that solution minerals are to be extracted. For the Salt Peter strengthens the spirit of Salt, that it can so much the more easier set upon and snatch to it the tender gold in those minerals.
The same spirit of Salt, may also without any rectifying be administred for this operation, to wit, such as ascends in the first Distillation.