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De re metallica / Georg Agricola. Transl. from the 1. latin ed. of 1556 ... by Herbert Clark Hoover ...
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BOOK X

461

Gold is also parted from silver on gilt articles by means of quicksilver.This is poured into an earthen crucible, and so warmed by the fire that thefinger can bear the heat when dipped into it; the silver-gilt objects areplaced in it, and when the quicksilver adheres to them they are taken outand placed on a dish, into which, when cooled, the gold falls, together with thequicksilver. Again and frequently the same silver-gilt object is placed inheated quicksilver, and the same process is continued until at last nomore gold is visible on the object; then the object is placed in the fire, andthe quicksilver which adheres to it is exhaled. Then the artificer takes a haresfoot, and brushes up into a dish the quicksilver and the gold which have

would not be surprising to find all the Alchemists subsequent to Geber mentioningacids. It will thus be seen that even the approximate time at which the mineralacids were first made cannot be determined, but it was sometime previous to the 15thCentury, probably not earlier than the 12th Century. Beckmann (Hist, of InventionsII, p. 508) states that it appears to have been an old tradition that acid for separatingthe precious metals was first used at Venice by some Germans ; that they chiefly separated thegold from Spanish silver and by this means acquired great riches. Beckmann considersthat the first specific description of the process seems to be in the work of William Budaeus(De Asse , 1516, in, p. 101), who speaks of it as new at this time. He describes the operationof one, Le Conte, at Paris, who also acquired a fortune through the method. Beckmannand others have, however, entirely overlooked the early Probierbiichlein. If our conclusionsare correct that the first of these began to appear at about 1510, then they give the firstdescription of inquartation. This book (see appendix) is made up of recipes, like a cook-book,and four or five different recipes are given for this purpose ; of these we give one, which suffi-ciently indicates a knowledge of the art (p. 39) :If you would part them do it this way :

Beat the silver which you suppose to contain gold, as thin as possible ; cut it in small pieces and place it in strong water ( slarkwasser ). Put it on a mild fire till it becomes warm and throws up blisters or bubbles. Then take it and pour off the water into a copper- bowl; let it stand and cool. Then the silver settles itself round the copper bowl; let the silver dry in the copper bowl, then pour the water off and melt the silver in a crucible. Then take the gold also out of the glass kolken and melt it together. Biringuccio (1540,Book VI.) describes the method, but with much less detail than Agricola. He made hisacid from alum and saltpetre and calls it lacque forti

Parting with Sulphur. This process first appears in Theophilus (1150-1200), andin form is somewhat different from that mentioned by Agricola. We quote from HendriesTranslation, p. 317, How gold is separated from silver. When you have scraped the gold from silver, place this scraping in a small cup in which gold or silver is accustomed to be melted, and press a small linen cloth upon it, that nothing may by chance be abstracted from it by the wind of the bellows, and placing it before the furnace, melt it; and directly lay fragments of sulphur in it, according to the quantity of the scraping, and carefully" stir it with a thin piece of charcoal until its fumes cease ; and immediately pour it into an iron mould. Then gently beat it upon the anvil lest by chance some of that black may Ay from it which the sulphur has burnt, because it is itself silver. For the sulphur con-i' sumes nothing of the gold, but the silver only, which it thus separates from the gold, and which you will carefully keep. Again melt this gold in the same small cup as before, and add sulphur. This being stirred and poured out, break what has become black and keep it, and do thus until the gold appear pure. Then gather together all that black, which you have carefully kept, upon the cup made from the bone and ash, and add lead, and so burn it that you may recover the silver. But if you wish to keep it for the service of niello, before you burn it add to it copper and lead, according to the measure mentioned above, andniix with sulphur. This process appears in the Probierbiichlein in many forms, differentrecipes containing other ingredients besides sulphur, such as salt, saltpetre, sal-ammoniac,and other things more or less effective. In fact, a series of hybrid methods between absolutemelting with sulphur and cementation with salt, were in use, much like those mentionedby Agricola on p. 458.

Parting with Antimony Sulphide. The first mention of this process lies either inBasil Valentines Triumphant Chariot of Antimony or in the first Probierbiichlein. Theate to be assigned to the former is a matter of great doubt. It was probably written abouttne end of the 15th Century, but apparently published considerably later. The date of theProbierbuchlem we have referred to above. The statement in the Triumphal Chariotis as follows (Waites Translation, p. 117-118) : The elixir prepared in this way has the1( same power of penetrating and pervading the body with its purifying properties that,, mitimony has of penetrating and purifying gold. . . . This much, however, I haveproved beyond a possibility of doubt, that antimony not only purifies gold and frees it

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