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Leaching Gold and Silver Ores. The Plattner And Kiss Processes: A Practical Treatise | by Charles Howard Aaron



This book is written in the endeavor to supply, in some small degree, a want which is severely felt on this coast, namely, that of plain, practical books on metallurgy. In the standard works on this subject, especially in regard to gold and silver, there is a great lack of those practical details which are so essential to the success of the operator, while some of them are characterized by a display of scientific lore which is very discouraging to those whose preliminary education does not enable them to understand it.

TitleLeaching Gold and Silver Ores. The Plattner And Kiss Processes: A Practical Treatise
AuthorCharles Howard Aaron
PublisherA. J. Leary, Stationer
Year1881
Copyright1881, C. H. Aaron
AmazonLeaching Gold And Silver Ores
Leaching Gold and Silver Ores
-Preface
This book is written in the endeavor to supply, in some small degree, a want which is severely felt on this coast, namely, that of plain, practical books on metallurgy. In the standard works on this s...
-Introduction
1. Leaching, or lixiviation, originally meant the extraction of alkaline salts from ashes, by pouring water on them. The resulting liquid was called a leach, lixivium, or lye. In metallurgy, at the pr...
-Roasting
15. As a metal chloride is a compound of a metal with chlorine, so a metal oxide is a compound of a metal with oxygen, and a metal sulphide, or sulphuret, is a metal combined with sulphur, while a met...
-Roasting. Continued
Chloridizing Roast 20. Chloridizing Roast. At the commencement this is the same as an oxidizing roast; but salt is mixed with the ore, either at the time of charging the furnace or at a certain stage...
-Apparatus
Roasting Furnaces 33. Roasting Furnaces. The essential condition of roasting pulverized ore is, that every particle shall be exposed to the action of heated air until certain chemical changes are eff...
-Apparatus. Continued
39. The door frames are two feet long by eight inches high in the clear, are set two inches above the hearth, and are built into the wall as solidly as possible. An exception is made as to the back do...
-Apparatus - Furnaces
It is a good arrangement. The floor on each side of a furnace is paved with bricks to a width of 14 feet. Furnace Tools 49. Furnace Tools. The tools required for such a furnace are: three or four ...
-Apparatus - Furnaces. Part 2
Suction Pipe 54. Suction Pipe. In cases of difficult leaching, filtration may be facilitated by means of a suction pipe. This is simply the discharge pipe of the leaching vat, made of stiff hose, or ...
-Apparatus - Furnaces. Part 3
Precipitating Vat 57. Precipitating Vat. Figure 1, Plate 4 - This is also a wooden tub, and, if for gold, is coated inside as the leaching vat. A smooth bottom is made in it, either by means of a lay...
-Apparatus - Vats
The smaller vat, Figure 2, Plate 4, is to contain a solution of iron sulphate. It is provided with a filter, and a discharge pipe which reaches to the gold precipitating tub, and which, when not in us...
-Apparatus - Generator
Press 63. Press. To facilitate the drying of the silver precipitate it is pressed into cakes. The press is similar to a cheese press. It is sometimes operated by means of a screw, but a weighted leve...
-Special Directions For Working
A 71. A. Concentrated Pyrites containing gold, but no silver. - This material is produced in the gold quartz mills, by crushing the rock in a wet stamp battery, in which the free gold is amalgamated ...
-Special Directions For Working. Part 2
Roasting 77. Roasting. When the sulphur begins to burn on the first hearth, the fire is kept quite low. The burning of the sulphur can be seen, even in the day time, if the furnace house is dark, as ...
-Special Directions For Working. Part 3
Chlorination 92. Chlorination. Time may be saved by starting the chlorine generator as soon as the vat is about half charged, as the filling will be completed before the gas can reach the surface. T...
-Special Directions For Working. Part 4
Leaching The Gold Ore 96. Leaching The Gold Ore. After the ore is supposed to have remained long enough in contact with chlorine - that is, from 12 to 40 hours - the plug hole in the cover is opened,...
-Special Directions For Working. Part 5
Precipitating The Gold 100. Precipitating The Gold. On beginning the leaching, about a dozen gallons of the solution of iron sulphate is let into the gold tub (for exceptions see article on precipita...
-Special Directions For Working. Part 6
Collecting The Gold 108. Collecting The Gold. Unless when working very rich ore, or for special reasons, the gold is not removed from the tub until several precipitations have been made. When a clean...
-Special Directions - Gold
115. It sometimes happens that the precipitated gold is contaminated by lead sulphate, which cannot readily be removed in the washing, and which, does not mix with the slag proper. This cannot be skim...
-Special Directions - Gold. Part 2
Leaching The Silver 123. Leaching The Silver. At this point some operators remove the ore to other leaching vats, from an idea that the small quantity of the leaching liquid used for silver which rem...
-Special Directions - Gold. Part 3
Precipitation Of Silver 129. Precipitation Of Silver. The silver is precipitated by means of a strong solution of calcium poly-sulphide, called, in the works, simply calcium, or sulphide, which i...
-Special Directions - Gold. Part 4
Collecting The Precipitate 133. Collecting The Precipitate. After several precipitations, or when desired, the black mud, consisting of silver sulphide, mixed with free sulphur, and more or less base...
-Special Directions - Gold. Part 5
C 136. C. Concentrations containing Silver, but little or no Gold. - These concentrations generally contain less iron pyrites, and more lead, zinc, copper, antimony, and arsenic, which makes them mor...
-Special Directions - Gold. Part 6
D 142. D. Concentrations rich in Gold and Silver, and containing much Lead, etc. It appears that certain rich ores, containing much lead, and other obstructive metals, do not yield the gold well when...
-Special Directions - Gold. Part 7
F 146. F. Ores Containing Coarse Gold, or an Alloy of Gold and Silver. - If the gold is too coarse, it will not be entirely dissolved in a single operation by the above described process of chlorinat...
-Special Directions - Gold. Part 8
Calcium Hyposulphite 150. Calcium Hyposulphite. This solvent may be made by passing air, and the fumes from burning sulphur, or from sulphuric acid and charcoal heated in a retort, through a solution...
-Special Directions - Gold. Part 9
Loss In Roasting 155. Loss In Roasting. The only reliable method of determining the loss of gold or silver in the roast-ing of ore on the large scale is, to dry, weigh, sample, and roast a quantity, ...
-Plan Of Works
157. Plate 7 will give the reader a good idea of the general arrangement of a plant for treating, per day of 24 hours, from 1 1/2 to 3 tons of concentrations containing gold and silver. The appended d...
-Assaying Concentrations
158. It is well known that many experienced as-sayers, although generally reliable, do not obtain correct results from the assay of gold-bearing sulphides, very rich ores of silver, or cement copper c...
-Assaying Concentrations. Part 2
First Assay 160. 1st Assay. Half an ounce of the finely pulverized and dried ore is roasted in a roasting dish, in the muffle. To prevent loss by decrepitation, the assay is covered by another roasti...
-Assaying Concentrations. Part 3
166. 5th Assay.Ore.......................... 1/2 ounce. Sodium bicarb............... . 720 grains. Litharge......................300 A little flour and pulverized glass will do no harm, and in so...
-Addenda. Flue Covering
172. A very convenient covering for horizontal flues, which can be removed and replaced easily, is shown in the annexed diagram. It consists of a kind of arched tile, made by bindingtogether, with an ...
-Filters
173. Filters for dumping vats are made with a bed of twigs, in place of gravel, and over the twigs is a piece of cloth, which is held close to the inner surface of the staves by a wooden hoop. The obj...
-Copper
174. When concentrations which are to be chlorinated for gold, contain also copper, the roasting is not pushed to the decomposition of copper sulphate. The latter is converted into chloride by an addi...
-Means Of Drawing Liquid From Precipitating Vats
175. Some operators use wooden faucets for this purpose. One objection to faucets is, that a portion of the precipitated gold lodges in the bore, and it is necessary, on opening the faucet, to place a...
-Recovery Of Absorbed Gold
176. The false bottoms, of perforated wood, and the chlorinating vats, should be burned when no longer required, as they contain a considerable quantity of gold. At my works at Melrose the ashes of th...
-Generators
177. There are several forms of generator. That described differs slightly from those in general use. In Deetken's generator, with water joint cover, the wall of the water chamber is not high enough t...
-Wash-Bottles
178. The wash-bottle described (68) is of my own contrivance. Kustel describes one, made from an acid-carboy, arranged like that which I have described for the working test. Deetken used simply the be...
-Sifting Ore
179. The usual method of sifting the damp ore into the vats, by means of a shaking sieve worked by hand, is tedious. The roasted ore might be sifted dry through a rotatory cylinder sieve, by hand or b...
-Cost Of Acid
180. Sulphuric acid of 6o Beaume, or 1.76 sp. gr., containing, according to Ure, 69.31 per cent of dry acid, costs four cents per pound in San Francisco. One pound of this acid is equal to 1.06...
-Salt, Manganese, And Acid
181. According to the chemical view of the production of chlorine from salt and manganese, under the action of sulphuric acid, 26.8 pounds of pure salt is sufficient for 20 pounds of pure manganese ...
-Salt, Manganese, And Acid. Continued
Assay Of Manganese 184. Assay Of Manganese. Take a short necked, flat bottomed flask of three ounces capacity, and fit into it a cork through which pass two glass tubes of about 1/8 inch bore. One of...
-Surplus Chlorine
186. The gasometer, suggested for the removal of surplus chlorine (98), might be made by attaching a leaden curtain to a disc of wood to which the suspending chains would then be fastened. A light ...
-Precipitating Gold
187. It occurred twice in my works that on collecting the precipitated gold it was found to be brick red, instead of having the usual brown color. It was also deficient in quantity. On the first ...
-Suspended Gold
189. By taking some of the waste liquor from the gold tub, filtering twice through Sweedish paper, and then smelting the paper with litharge, I found that after 24 hours settling there remained gold ...
-Precipitants For Gold
190. When the ore contains copper, the waste solution from the tanks in which the copper is precipitated can be used for refilling the vat containing the precipitant for gold, as it contains a large ...
-Sand In Gold Melting
191. Many years ago I was employed as melter in a bullion assaying establishment, and was often called on to refine gold, which was done by granulating and re-fusing with nitre and borax, in a sand ...
-Drying Chamber
192. For drying the gold, I suggest that a convenient arrangement would be a sheet-iron closet, in the form of a muffle, in the dust chamber, with a door which could be locked. In this the dishes ...
-Volatilization Of Gold
193. It has been stated by some authors that there is never much loss of gold in roasting ores, unless the roasting is performed too rapidly, and that the addition of salt makes no difference in this ...
-Solution Of Silver In Hypo
194. The statement that silver chloride dissolves in a solution of calcium hyposulphite is not strictly accurate. It is decomposed, exchanging constituents with the calcium salt, forming calcium ...
-Waste Of Sulphur
195. The quantity of sulphur required for the precipitation of silver is really only as 16 to 108, but a great waste occurs in the process described, from two causes: Firstly, there is always a ...
-Recovery Of Sulphur
196. There are two methods by which the free sulphur may be recovered from the precipitate. The first, introduced, it is believed, by Ottokar Hofman, consists in subjecting the mass to heat, in a ...
-Matte From The Silver
197. The matte obtained in melting the silver precipitate is usually quite rich, and it seems to be impossible to completely desilver it by means of iron alone, at least in the presence of copper. ...
-Melting Furnace
198. I have seen, in the mining regions, many barbarously constructed melting furnaces, some of which were very inconvenient to work with. A description of the furnace which I build for silver ...
-Sodium Hyposulphite
199. Sodium hyposulphite may be made by passing sulphurous acid (sulphurous anhydride) and air through a solution of sodium sulphide, produced by fusing together five parts of sodium sulphate (a ...
-The Chlorination Assay
200. The so-called chlorination assay, is so far incorrect that it gives not only the silver chloride, but all other silver compounds which are soluble in solutions of the alkaline or earthy ...
-Chlorination Tailings
201. However carefully the ore may be treated, a certain portion of gold remains in the tailings, varying, other things being equal, according to the character of the ore. In case this results, in ...
-Value Of Bars
202. Large bullion scales, and troy weights, are not always at hand; yet it is often desirable to know the value of a bar before sending it away from the works, and as good counter scales, with ...
-Chlorine
203. Chlorine plays such an important part in connection with human industry, that a short sketch of its history and properties cannot but be interesting and useful. Chlorine is an elementary body, ...
-Plattner's Process
204. The process of gold extraction known as Plattner's chlorination process, which is that described in the text, originated in Europe, and was first introduced here by G. F. Deetken, M. E., at ...
-The Kiss Process
205. The use of alkaline or earthy hyposulphites for the extraction of silver from ores, also originated in Europe, having been suggested by Dr. Percy, in 1848, and first applied in practice by Von ...
-The Bruckner Furnace
206. This furnace consists of a horizontal, brick-lined, hollow cylinder, of boiler iron, with central openings at the ends, through which the flames from a fixed fireplace pass to a flue connecting ...
-The Brunton Furnace
The Brunton Furnace. 207. This furnace is essentially similar to the Bruckner, but has no diaphragm. In form it differs slightly, being ovoid, or egg shaped, the larger end toward the fire. This f...
-The Pacific Chloridizing Furnace
208. This is a simple brick lined rotating cylinder, not differing essentially from those described. It is however made of large capacity, as much as seven tons of ore being treated at once. A good ...
-The White Furnace
209. The White furnace consists of a hollow rotatory brick-lined cylinder of cast-iron, with open ends. The brick lining is so arranged, in the short segments of which the cylinder is composed, as to ...
-The Howell-White Furnace
210. The furnace known by the above appellation, is a modification of the White. The cylinder is lined with bricks in only one-third of its length from the lower end, adjoining the fireplace, the ...
-The Thompson-White Furnace
Another modification of the White furnace has been made by J. M. Thompson. This furnace differs from the Howell-White in several particulars. The cylinder is of one diameter throughout its length, an...
-The O'Hara Furnace
212. This is a reverberatory furnace of great length, the hearth being about one hundred feet long by five to eight feet wide. It is traversed lengthwise by plows and scrapers attached to endless ...
-Stetefeldt Furnace
213. If any metallurgist had been told, prior to the introduction of the Stetefeldt furnace, that a chlorid-izing roasting of silver ore could be effected in the short space of a few seconds of time, ...
-Description Of The Furnace
A is the shaft into which the pulverized ore is showered by the feeding machine, placed on the top of the cast iron frame B. The shaft is heated by two fireplaces (C). The ashpits of these are closed ...
-Description Of The Feeding Machine
The Feeding Machine is shown in Fig. 2. The castiron frame (A), which is placed on top of the shaft, is provided with a damper (B), which is drawn out when the furnace is in operation, but inserted w...
-Remarks On Furnaces
214. The quantity of fuel consumed in roasting varies with the quality of the fuel, the character of the ore, and the kind of furnace used. In a single hearth reverberatory furnace, each ton of ...
-Advertising
Justinian Caire, Importer and Dealer in Assayers' Materials & Chemicals Mill Supplies Of Every Kind. Brass and Steel Battery Screens, Agency of L. Oertling's, London; Beckers' & Sons, New York, ...
-Advertising. Continued
Charles H. Aaron, Having had eighteen years' experience in Mining, Milling and Assaying, offers his services in the following branches: Examination Of Mines, Erection And Inauguration Of Reduction W...







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