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BOOK X
461
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Gold is also parted from silver on gilt articles by means of quicksilver.
This is poured into an earthen crucible, and so wanned by the fire that the finger can bear the heat when dipped into it ; the silver-gilt objects are placed in it, and when the quicksilver adheres to them they are taken out and placed on a dish, into which, when cooled, the gold falls, together with the quicksilver. Again and frequently the same silver-gilt object is placed in heated quicksilver, and the same process is continued until at last no more gold is visible on the object ; then the object is placed in the fire, and the quicksilver which adheres to it is exhaled. Then the artificer takes a hare's foot, 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 mentioning
acids. It will thus be seen that even the approximate time at which the mineral acids were first made cannot be determined, but it was sometime previous to the 15th Century, probably not earlier than the 12th Century. Beckmann (Hist, of Inventions II, p. 508) states that it appears to have been an old tradition that acid for separating the precious metals was first used at Venice by some Germans ; that they chiefly separated the gold from Spanish silver and by this means acquired great riches. Beckmann considers that 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 operation of one, Le Conte, at Paris, who also acquired a fortune through the method. Beckmann and others have, however, entirely overlooked the early Probierbiichleitt. If our conclusions are correct that the first of these began to appear at about 1510, then they give the first description 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 sufficiently 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 (s(arkwasser). 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 his acid from alum and saltpetre and calls it lacque forti Parting with Sulphur. This process first appears in Theophilus (1150-1200), and
in form is somewhat different from that mentioned by Agricola. We quote from Hendrie's Translation, 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 apiece 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 " fly from it which the sulphur has burnt, because it is itself silver. For the sulphur con" sûmes 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, and " mix with sulphur." This process appears in the Probierbüchlein in many forms, different recipes 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 absolute melting with sulphur and cementation with seilt, were in use, much like those mentioned by Agricola on p. 458. Parting with Antimony Sulphide. The first mention of this process lies either in
Basil Valentine's " Triumphant Chariot of Antimony " or in the first Probierbüchlein. The date to be assigned to the former is a matter of great doubt. It was probably written about the end of the 15th Century, but apparently published considerably later. The date of the Probierbüchlein we have referred to above. The statement in the " Triumphal Chariot " is.as follows (Waite's Translation, p. 117-118) : "The elixir prepared in this way has the "same power of penetrating and pervading the body with its purifying properties that "antimony has of penetrating and purifying gold. . . . This much, however, I have " proved beyond a possibility of doubt, that antimony not only purifies gold and frees ii |
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