Rensselaer Union, Volume 10, Number 29, Rensselaer, Jasper County, 4 April 1878 — Coining Honey at the Hint. [ARTICLE]

Coining Honey at the Hint.

Silver is sent from the Assay Office to the Philadelphia Mint pure, or 999 line, which is about as pure as silver can be. It is sent in large bars, and when received at the mint is melted and alloyed with copper. Coin silver is 900 fine. After being melted and alloyed tho metal is cast into ingots, which are simply bars of a convenient size for handling. The metal is then assayed, todatermine whether it is exactly of the standard fineness. Assaying is doqe by what is known as the dry or humid prpeoss. Samples for assay are taken while the silver Is in a fused condition, and two assays are made of every specimen. The silver ingots then go to •ho coiner. They aro first rolled into strips, and as the rolling process is apt to make the metal brittle, it is annealed to sqften it. Silver is annealed simply by heating in an open wood fire, and then being allowed to cool gradually. The silver dollar strips aro passed through the rolls nine or ten times before the first annealing, and four or five times afterward. Then the process of annealing is repeated. After the last annealing the strips are run through cutters, which divide them into drafts of the proper thickness for the coins; and these, in their turn, arc run through a steam punching machine which cuts planchets the proper size for the coin. From 160 to 240 are cut in a minute. As the metal gets greasy during this process, the planchets are then dipped into a bath of diluted sulphuric acid, which is too weak to act upon the surface, but effectively removes all foreign matter. The planchets are then adjusted; that is to say, they are carefully weighed, and all that are lacking in weight are cast aside; sueh pieces are called “lights,” and the “heavier.” are the pieces which weigh too much; and aro filed off. The adjusting is done by women. It is a process which requires much delicacy, and scales are used which arc sensitive to one-sixty-fourth of a grain. After the annealing is finished, the next operation is the milling, which is done with a curioußsortof machine. Theedgesof the coin are thrown up and grooved by this process. After another cleaning with sulphuric acid the coins are read}- for the die. The stamping is done on a screw-press, and both Sides of the coin are stamped at the same time. The dies are cylindrical blocks of steel upon which are carved the designs to be transferred by pressure to the coins. Art of a high order, as well as fine mechanism, is conspicuous in this part of the coining process. The designer, in the case of the new silver dollar, Mr. Morgan, first draws his design on paper, from which is made a model in wax, of which a plaster cast is taken, and from this cast an electrotype is taken, upon which careful revision is made with the graver. This electrotype, like the model and cast which preceded it, is three or four times larger than the impression which appears on the dollar. The design is transferred to a steel die by using Hill’s reducing machine, constructed on the principle of the pantagraph. One arm of this instrument, with a blunt point, follows the lines on the electrotype, while the other arm, to which is attached a strong and rapidly-revolving drill, reproduces the same lines, on a smaller scale, upon a steel block. By means of a press this impression is transferred to another block, in intaglio, and thence upon another block, which is the parent die. After each transfer the lines are carefully improved with a graver. Steel of the same quality as that of which the parent die is made is used for the coining dies. They are annealed, and trued on both ends. . Two or three blows in the screw-press, which is worked with a large wheel, secures a perfect impression, and both the obverse and reverse of a 6oin are struck at once. Machinery places the planchets between the dies, and afterward drops the completed coin in a box. Two or three pieces of each coin, are reserved for the annual Government assay. The processes of melting, refining and assaying gold and silver are carried on in the Assay Office, in .this city, on_ quite as large a scale as at the Philadelphia Mint. Not only Government work is done here, but large deposits are made daily of gold ami silver bullion by private individuals. Gold is always found alloyed with silver, and it

is never found with any other alloy. To separate the silver from the gold, the bullion is boiled in sulphuric acid, which removes the alloy; the gold is then reboiled and reduced to a coarse powder resembling clay. Its purity then is 998 or 999. The silver, mixed with copper, is run into vats on a lower floor, and is purified and granulated, when it resembles pipe-clay. The granulated gold and silver are pressed into large cheeses in a hydraulic-press. A cheese of gold, twelve inches in diameter and three inches thick, is worth $20,000; a silver cheese of the same size is worth S9OO. The sulphuric acid, after it is used, produces a sediment of blue vitriol, which is much prettier than either the gold or the silver seen in the Assay Office. The v ittriol and the weak acid are both sold for as much money as the original acid costs. The substitution of sulphuric acid for nitric has caused a saving to the New York Assay Office alone of SIOO,OOO a year. Depositors receive their gold and silver separately at standard purity, 900. Pure metal is also sent to the Asjgay Office from the various refineries to be alloyed. From United States refineries silver is generally sent in large bars or cakes; and a small amount of Mexican metal is received in thin, irregularly-shaped pieces called disks. The fumes from the vats and furnaces in the Assay Offico are condensed and sold as weak acid. Only r a small amount of the gas escapes into the atmosphere, and, although it is slightly offensive, it is not injurious. On the contray, this gas is an excellent disinfectant, and acts upon dead matter rather than living. The same precautions are taken to prevent loss in the Assay Office as in the great mints/ The ashes, the sweepings from the floor, the crucibles, and all the instruments which come in oontact with the precious metals are washed and ground in a machine constructed for the purpose, and the stray particles of silver and gold are gathered together. — N. Y.'Times.