Alloys of gold and silver amalgam In the category gold discovery more articles and learn more information about Alloys of gold and silver amalgam Reviews Price Specifications Features Image manuals videos Accessories All this in metal detectors for gold.
Alloys of gold and silver amalgam Review
Gold is the metal more easily combined with mercury, obtaining amalgams by direct binding of the two metals. If gold comes from the reduction of some of its salts, as the precipitate is very thin, the combination does not verify with ease, because gold powders float long on mercury. On the other hand, reduced, in the form of crystals gold something more precipitate particles, large sink and dissolves much more quickly. Gold crystals are obtained by dissolving gold chloride Amyl alcohol, and heating the solution to a boil, the gold is separated into crystals very small and bright.
In the metallurgy of gold, one of the procedures most used since antiquity, consists of treat the gold-bearing sands with mercury, and warm the product in iron retorts for distillation mercury. red gold sol adding mercury.
Golden fire with amalgam
Gold forms with mercury a chemical combination that has great tendency to crystallize, should be avoided which, because it is very difficult to Browning fire Crystal amalgam. To prepare an amalgam of gold very suitable for the Golden Fire proceeds as follows: gold in a graphite Crucible internally coated clay to prevent the adhesion between the mercury and graphite is placed, and is heated to red.
It is not necessary that the gold is pure: can be used alloyed gold, being preferable alloys of gold with silver to gold and copper, since these last are hardened in a short time considerably. Just the presence of small amounts of copper so that the amalgam may not apply evenly to metal surfaces. The best is to use gold in very thin sheets, which are cut before lowering them into the Crucible; When this reached wing red, is poured inside the eighth or ninth part of the mercury that is to be used, previously heated to the point of boiling; it stirred continuously with a rod of iron, and after few minutes is removed from the fire. If they left to cool the amalgam in the Crucible, crystallize, so, as soon as the Crucible, is removed from the fire the amalgam in a bin with water, is poured to make cooling fast.
Gold amalgam crystallizes always within some time, so it only needs to be prepared enough to be used as quickly as possible. If it has come to be the crystallization, part of the mercury will be separated from the amalgam, which can be regenerated by heating it in a crucible with an excess of mercury.
For the Golden or silver fire, only employs a pure so-called amalgam, i.e. non-mercury, for which compresses the ordinary amalgam in a Suede bag, using pressures increasingly more elderly people; Mercury that comes out of the bag, always contains a certain quantity of gold or silver, and can be used to prepare new amalgams.Red Mercury
The gold or silver fire only applies to metals that support well without melting temperatures close to the boiling point of mercury. Prepare the metals in advance, to facilitate the adherence of the amalgam, consisting of this preparation to heat the Red objects in question, with which grease, dust, etc., attached to the surface of the metal, are burned, thus covering the metal with a film of oxide, he escapes by immersing him in a bath of nitric acid and 1-3 part part of sulfuric acid , which dissolves the oxide, leaving free the metal surface. Items that have to be browned very stable so should be immersed in this bath for quite some time, so that the surface acquires some roughness, which is indispensable for good adhesion of a large amount of amalgam; they are then immersed in water without touching them with their hands, and are kept. It is so far to the Golden, to avoid the oxidation of its surface. The process of amalgamation is to cover the object with a layer of Mercury metal, made from a solution of 100 parts by weight of mercury in 110 parts of nitric acid, and adding to the solution 25 parts water; This solution applies to objects with fine brass wire brush. Object metal work on the salt of mercury, reducing it, and the mercury becomes State metal, in the form of very small drops, whereupon the metal takes a white appearance of silver.
Once amalgamated so objects, be they come after Golden or silver, applying the amalgam of gold or silver with a brush on those very hard and in a quick and uniform manner, after which fire objects placed volatilize mercury and is gold or silver attached to its surface. Items must be removed from time to time of fire, to apply again amalgam on the sites that has not been attached.Red Mercury
This work is unhealthy for workers who engage in it, so the gold into the fire, although it is of greater duration than others, is not just used. Many articles, that are not well to Brown for the first time, Brown two or three times more, until coated with a rather thick gold film. With a suitable treatment to the fire, can occur a certain color Dorado using so-called gilders wax.
Silver amalgam
The silver amalgam can be done easily using finely divided silver. Mercury requires only be heated to 210-300 ° C, and once this temperature is reached, sprinkle silver on that one and the mixture is stirred well. The vessel where this operation is done is heated for several minutes and then allowed to cool, compressing it into a bag or sack of leather. Silver amalgam can be also used with ease, by dissolving silver in nitric acid, evaporating the solution to eliminate the excess of free acid, diluted with distilled water, and adding mercury in the ratio of 4 parts, in weight, of 1 of the silver used at the start of the operation. Mercury precipitates to the silver in metallic state and immediately after form amalgamates it; the liquid is above, some time after, not containing silver, but it is constituted by a solution of nitrate of mercury mixed with all copper which could contain silver, dissolved in the form of copper nitrate. If pouring a few drops of HCL to some of this liquid in a test tube, a white precipitate is formed, it indicates that all silver has been deleted from the solution, to have passed to the amalgam.how to extract gold from black sand with mercury
in the silver mirror system, which has almost universally replaced the Tin, uses the property of silver amalgamate with ease, by subjecting glass, after silver, to the action of a dilute cyanide solution double of mercury and potassium, so that to form an amalgam of silver white and bright that strongly adheres to the glass. To facilitate the operation and take all the silver, at the same time saving double cyanide, recommends Lenoir: glass, spray at the time be covered with the mercurial solution, with very fine zinc powder, which precipitates to mercury and regulates the amalgamation.
in the metallurgy of silver also uses the property of this metal combined cold with mercury, especially in the treatment of poor existing minerals. In Saxony, to treat silver ores, use mercury for You amalgams ore, after ground is stirred with discs of iron and mercury and water. Amalgam, collected and filtered under strong pressure, contains 30 to 33 per 100 of silver; It is distilled in cylindrical cast iron retorts, provided an outlet pipe submerged in water to condense the mercury vapour, or iron plates, arranged one over the other mounted on a vertical axle of iron supported by a tripod on the bottom of a tank filled with water and covered with a receptacle of iron, surrounded in turn from incandescent carbon. It must be borne in mind that the latest portions of mercury, in an amalgam of silver subject to distillation, volatilize only under the action of a high temperature and prolonged.
