The works of the highly experienced and famous chymist, John Rudolph Glauber

by Johann Rudolf Glauber

Of the separation of metals.

This is a most ancient and profitable Art, whereby one metal may be separated from another: And it is for the most part done 4. ways, viz. by Aqua Fortis, by cement, by flux with sulphur, and lead, and lastly by Antimony; which ways that most witty Lazarus Ercker, hath clearly, and distinctly described, whose description is not to be found fault with, although some necessary things may be added thereunto, which being but few, I thought it superfluous to add them in this place.

And that separation consists in three chief metals, Gold, Silver, and Copper; he made no mention of other metals, and two of the aforesaid four ways are in use, as very easie, for they are done with Aqua Fortis and Cement, the two others most commonly neglected, which are done by benefit of melting with Sulphur and Lead; and also by Antimony: that which is admirable, because metals are easier separated by benefit of these two ways, than by Aqua fortis and Cements, suspected of wast, whereas not Sulphur and Antimony, but the ignorant worker, not knowing the nature of Sulphur and Antimony, is rather to be blamed, because he knows not how to order them, and withall leaves the nearer way of separation: and I must needs confess it that without this furnace I would not separate with them, because with that common way of furnaces and bellows, the stink of Sulphur and Antimony hurtful to the Liver, Lungs, Brain, and Heart, is received by the Nostrils to the hazard of health: for which cause I do not wonder that those two wayes requiring greater diligence than those two former by Aqua fortis and Cements are rejected. But this Furnace being known, with which without danger one may melt, I doubt not of excelling the two former ways hereafter as more profitable than them. For he who knows Antimony, may not only easily with small cost separate Gold from the addition without any loss of it, and speedily refine it, but also easier separate gilt silver, than by Sulphur, Lead, &c. in great store without any loss of Gold or Silver.

And this is the easiest way of the separation of Gold and Silver which is done by the benefit of melting, requiring no more charge than the coals; for there is Antimony which hath Gold in it as much as it is worth, which will be the separators gain: I would have you know this, how Antimony may again be separated from Gold and Silver, not by the common way, which is done by bellows, but by the special way of separation wherewith the Antimony is preserved, so that it may be used again for the same purpose; which I will treat of in another place. Besides the four ways spoken of, there is also another way, best of all, by the nitrous spirit of salt, namely after this manner: ℞ the spirit of salt (prepared by our first and second Furnace) acuated with Nitre disolved in it, to which add grain Gold mixed with Silver and Copper; put it in a glass vial in hot sand to dissolve, and the Gold together with the Copper will be dissolved in it, and the Silver left in the bottom of the vial: decant off the solution, to which add something, precipitating Gold, and make them boyl together, and the pure fine gold will be separated and precipitated like the finest meal, serving Writers and Painters; the Copper being left in the water; which thou mayst if thou wilt precipitate from the water, but it is better to take away the water, which will serve again for the same use. If the precipitated Gold be washed and dryed it gives in the melting (by which nothing is lost) the best and purest Gold. For finer gold can neither be made by Aqua fortis nor by Antimony.

Therefore this is the best way of all, not only for the small cost, but also for the easiness yielding the best Gold of all others.

Then take the calcin’d Silver left in the gourd, sweeten and dry it, which done make a little salt of Tartar to melt in a crucible, to which by course put a little of the refined silver with a spoon, and it will be presently made a body without any loss. You may also boyl that Calx as yet moist newly taken out of the gourd with a Lixivium of Salt of Tartar, even to the evaporation of all moisture: and melt the dry remnant, where also nothing is lost. Without this medium the calx of Silver (drawn from Aqua Regia) is not fusible of it self, turning into a brittle matter, like horn that is white, or of a middle colour between white and yellow, called therefore of Chymists the Horn of the Moon; in reducing which many have tried much, which reduction we have already taught. For want of spirit of salt take Aqua Regia made of Aqua Fortis and salt Armoniack, which doth the same, but with greater charges. This also is to be preferred before other ways, which makes to the separation of any Gold of any degree, if so be it exceed Silver in weight; which is necessarily required in the solution made with Aqua Fortis.

But that you may see the prerogative of this separation, mark a little, when you separate by the Quarto and by Aqua fortis you must put just two or three parts of refined Silver to one of course Gold, where first the cost and labour of refining the Silver to be melted and grained with Gold are required: then a good quantity of Aqua fortis to dissolve, precipitate, edulcorate, dry and melt a great deal of silver. Consider then I pray, the labours and charges of my separation and the vulgar. When thou separatest with Cements there is need of boxes, and continual fire of one degree, which labour is tedious for times sake, and costly for coals, which labour you must twice or thrice take in regard of the mixt dross. Now again consider the labour and charges of both separations. When thou separatest by Sulphur and Antimony, which is the best way, without great charges, if thou knowest to separate Gold from Antimony without blowing, but this is tedious because thrice greater labour than our way, tedious indeed by reason of the difficulty of a perfect separation of Gold and Silver from the Antimonial dross. Think therefore what way of separation you will use to refine Gold speedily, surely you will chuse mine.

This way of separation hath also this prerogative, that it hath no need of refined silver which is done by the benefit of burning, but only its granulation, solution or separation by the use of Aqua Fortis, where though copper mixt with silver makes wast, yet by the help of this salt it is soon precipitated. By this means gilt silver is soon separated, the gold being dissolved by the nitrous spirit, and precipitated with the aforesaid matter precipitating. As for the separation of gilt silver which is to be done by help of fusion, and none is easier done than with Sulphur and Antimony, where when the necessary manual (ingredients) are known; a great deal is separated in a short time, but if thou knowest not how to handle Antimony and Sulphur (for which our Furnace very well befits) leave them, and use the common way; therefore lay not thy fault afterward on me, writing for thy good.

Of separating the courser metals.

The manner of separating Tin from Lead, and Copper from Iron, without loss of both metals, by preserving both, hath hitherto been unknown, which seems impossible to me by reason of the combustibility of both metals; and superfluous for the small profit, and saving charges. But how Gold and Silver may be separated from Tin with which commonly this abounds, without any wast, hath been long since sought to no purpose: but a possibility will appear to a serious considerer; and though I never tryed in great quantity, being content with a precipitation made with a little; I am yet perswaded this business will succeed in a great quantity and with much profit; namely by the help of a Furnace made on purpose where gold and silver precipitated with lead and Halb Kopf by extream heat of fire; that tin is extracted to the remanence of the tenth part, which remainder you must peculiarly take and keep. Which done you must precipitate new tin in the foresaid Furnace, and so extract to the remainder of the Regulus, which being extracted from, is to be added to the first and reserved; which labor is to be reiterated, till thou hast a sufficient quantity of Regulus filling the Furnace; which again thou must precipitate; for by this means gold and silver are brought together, so that they may easily afterward be separated from the superfluous tin. By this means I count the separation profitable, where but little substance is lost, which is turned into ashes and smoak. Nor doth adding lead and Halb Kopf hinder, because sometime lead is mixt with tin, and the Halb Kopf is separated again. It is good therefore to separate pots and old dishes, by reason of the mixture of lead, and to precipitate the gold and silver from them, by the adjection of Halb Kopf only, where the residue is no way altered by the Halb Kopf, therefore thou mayst sell it, or refine it again: which in my judgment will be to great advantage.