Fine silver

Silver is also recovered during electrolytic refining of copper. Commercial fine silver contains at least 99.9% silver. Purities of 99.999+% are available commercially. 

Commodity exchanges require good deUvery silver buUion to be 999 parts per 1000 fine silver. Samples of specifications for silver are given in Table 6. ... 

Potassium cyanide is primarily used for fine silver plating but is also used for dyes and specialty products (see Electroplating). Electrolytic refining of platinum is carried out in fused potassium cyanide baths, in which a separation from silver is effected. Potassium cyanide is also a component of the electrolyte for the analytical separation of gold, silver, and copper from platinum. It is used with sodium cyanide for nitriding steel and also in mixtures for metal coloring by chemical or electrolytic processes. 

Polymer thick films also perform conductor, resistor, and dielectric functions, but here the polymeric resias remain an iategral part after cuting. Owiag to the relatively low (120—165°C) processiag temperatures, both plastic and ceramic substrates can be used, lea ding to overall low costs ia materials and fabrication. A common conductive composition for flexible membrane switches ia touch keyboards uses fine silver particles ia a thermoplastic or thermoset polymeric biader. 

Each distilling operation lasts twelve hoarB, and the product is about forty-five pounds of plate or teller silver from each hell. Tire teller silver contains only about seventy-five per cent, of fine silver, the remainder being chiefly copper it is melted in an open iron crucible, and cast into ingots—a process by which seme of the impurities are removed, and tho ingots contain about eighty per cent, of fine silver. 

Take 70 ounces quicksilver put in the furnace and blast it until the quicksilver is hot, then throw upon it one ounce of this stone and it melts like butter, penetrates all the parts (Glieder) of the quicksilver and turns it into fine silver which stands all the tests. ... 

Most modem silver mined has been used to make photographic film emulsions, in plating, and in alloys for tableware, jewelry, and electrical equipment. Sterling silver is an expression of purity, being at least 92.5% silver. This is expressed either with the word sterling, 0.925 (the is often omitted), or the Lion Passant hallmark. Fine silver is 99.9% pure, but is too soft for most applications. This is the standard purity for silver bullion, as a commodity. 

Silver is an excellent conductor of heat and electricity and a good reflector of light. It is relatively immune to oxidation but becomes tarnished by exposure to sulfur compounds in exceedingly small concentrations. It is an excellent electroplating metal and can also be deposited in thin films by evaporation. In Dewar flasks and other vacuum glassware, it is deposited from an aqueous medium by the Brashear process. Silver is an excellent brazing material and an important constituent of silver solder. The term silver is often applied to alloys of silver with copper for example Sterling silver contains 7.5 percent copper. Fine silver is 99.9+ percent silver. 

MOON — Homed Moon. The chemists apply this name to Calx of Silver made by aquafortis in the manner following Dissolve one ounce of fine silver in two ounces of aquafortis. When the... 

Now this water is a certain middle substance, clear as fine silver, which ought to receive the tinctures of sol and luna, so as the may be congealed, and changed into a white and living earth. For this water needs the perfect bodies, that with them after the dissolution, it may be congealed,... 

If, at this point, you wanted to ferment fine silver, one part of this Elixir would tinge ten parts Mercury into Lunam puram. It would, however, be a great pity if this work would be destroyed before its fruit is ripe. That is why the Sages advise not... 

Take one part of this nncture, project it on one thousand parts fine silver, and it will transmute it into fine gold. 

Then I traveled about, up and down in Italy, and came to an Italian tradesman, and a Jew, who understood German. These two made English Tin look like the best fine Silver, and sold it largely I offered to serve them. The Jew persuaded the Trader to take me as a Servant, and I had to attend the fire, when they operated with their art I was diligent, and they kept nothing from me, as I pleased them well. In this way I learnt their art, which worked with corrosive and poisonous materials, and I stopped with them fourteen weeks. 

Heating of ammonium hexachlorotechnctate(rV) in an inert atmosphere, e.g. nitrogen, at a dull red heat, also yields technetium metal. The complex salt does not melt, but decomposes under these conditions to leave technetium metal as a fine silver-grey powder [3] ... 

If a really untarnishable silver could be produced it would no doubt have a ready sale the chief difficulty lies in the insistence of the public that the metal shall be hall-marked, that is, it must be certified as containing at least 92 5 per cent fine silver. This allows only 7 5 per cent as a maximum for alloying elements, and hitherto that has proved insufficient. Although several nontarnishing alloys have from time to time been placed on the market, none has so far given satisfaction. 

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