The Mints of the United States


The Bureau of the Mint constitute« one of the most important branches of the United States Treasury, and unusual interest attaches to the dozen institutions which it maintains, in various parts of the country, and to which is entrusted the work of minting all the gold, silver, nickel and copper coins issued by this government. Up to the present time the bulk of the coining operations have been carried on at mints located at Philadelphia, San Francisco and New Orleans, but important supplementary work in the handling of bullion, etc., has been conducted by assay offices located at New York, Carson, Denver, Helena, Boise, Charlotte, St. Louis, Deadwood and Seattle.

Changing conditions in the country both in regard to the seat of greatest business activity and the principal sources of precious metals have gradually, however, exerted influence in favor of readjustment of this system, and indeed is well under way. For some years past Directors of the Mint have been recommending a curtailment of the coining operations at the mint at New Orleans, and the substitution of the new mint at Denver as one of the three centers of activity in this sphere.

Undoubtedly when a permanent arrangement is perfected, within the next few years, the country will be left with three coinage mints—one at the Pacific coast, which will be the national depository of the gold product of Alaska, the Pacific Coast States and of the imports from Australia and the Orient, one on the Pacific Coast convenient to the gold producers of the Rocky Mountain region; and one near the eastern coast, convenient to receive the imports from that direction.

The manufacture of all denominations of the United States coin is seen to the best advantage at the magnificent mint at Philadelphia, illustrated at the head of this article. This mint, a comparatively new institution, cost the United States approximately $2,500,000 and is unquestionably the finest building ever constructed for coinage purposes in the world. The machinery and other equipment is without peer in any land. The force of about 700 employes regularly engaged at the Philadelphia mint if about three times as great as that at either of the other coining mints, and the operating expenses and output of coins are proportionately in excess of the records at other institutions. The statistics just compiled show that during



Organized in1854 Coins of this mint are designated by the Mint Mark “S.”

the calendar year 1907 the big institution in the Quaker City made a most remarkable record. There were coined all told, 183,598,943 pieces of money (an increase of 16,948,710 pieces over the year 1906), representing a value of $63,263,104.93. During the year considerably more than four million gold pieces were coined, of which more than half a million was made up of the now design of eagles and double eagles. Nearly four million coins were struck off for the Philippine government, and upward of two million pieces were minted for the government of Panama.

The modem mint, in which neither pains nor money is spared to provide the most approved machinery and the most economical methods is in marked contrast to the coinage appliances of early times. It was not until 1836 that steam power was used, screw presses having been employed prior to that date, and the milling done by hand. A single milling machine, such as is in use today, will mill as many pieces in one hour as several men then produced in a week. Similarly, one modern coining press strikes, in an hour, more pieces than four men could strike in a day, under the old primitive conditions. During the first fifty years that the United States was producing coins there were turned out a total of ninety million dollars. Now the officials of the Philadelphia mint consider it nothing exceptional to coin that many dollars in a single year.

The Philadelphia mint is at once a palace, of the order appropriate to a structure of the government—a treasure house, a workshop and a factory of the highest class. The building which is of granite, occupies a full city block, and covers 58,000 square feet. It is three stories in height above the basement. In the basement are the vaults for the storage of coin and bullion. There are a score of these steel-lined vaults, most of them more than 100 feet in length, and more than 3,000,000 pounds of steel were used in the construction of these “strong boxes.” The vaults are, of course, protected by every modern safeguard and are so constructed that watchmen can pass completely around them.

One of the greatest advances in recent years, in mint processes, has been made in the melting department, where gas furnaces have supplemented those in which coal was burned. Each furnace now employed must be capable of melting 250 pounds of bullion at a charge, and of making at least five melts in eight hours, thus handling over half a ton of metal each day. Seventeen of these modem gas furnaces—each of a capacity of 25 per cent in excess of the old-time coal furnace—are now in operation at the Philadelphia mint. An important adjunct of the melting department is the refinery, in which gold and other metals



Organized in 1838, suspended operations in 1861, when it was seized by the Confederates. Reopened in 1879. Mint mark “O.”

are parted and refined from their baser components, preparatory to the operation of coining

After the design of a coin or metal has been duly approved, the work of preparing dies at the mint proceeds in accordance with one of two plans. By the oldest of these methords the surface of the face of the die is covered with a thin coating of transfer wax, which by means of pressure, is made to receive a tracing outline in pencil. The transfer is, of course, very delicate, and the lines must be gone over with a sharp-pointed instrument. The next process is to remove the steel, where the form or relief is required. This is done with chisel and gravers, Finally the die is hardened, and is then ready for use in making coins and metals. A second process necessitate as its first step, the preparation in wax of a model of the accepted design, the model beings three or four timen as large as the finished work is intended to be. When this model is finished an electrotype is made, and then, by means of a reducing: lathe, a reduced copy is made of the size required for the coin. Some of the most delicate portions of the design, which cannot be entrusted to the reducing apparatus, are worked in by hand. Then the die is hardened and tempered and is ready to fulfill its mission in producing coins.

The most interesting of all coining operations is the production oí gold coins. It may be taken as representative of all manipulations of this class. The ingots as received from the smelter and refinery vary in size and weight according to the denomination of the coin for which they are to be used. J he first operation in the transformation of ingots into coin is called “breaking down” and consists in passing these oblong pieces of precious metal between heavy rolls with the result that the ingots are formed into “strips.” Double eagles and eagles are passed through the finishing rolls three times, half eagles and quarters go through four time3. After an operation similar to that of wire drawing, the strips of gold are taken to cutting presses and by means of a steel punch, working into u matrix, the planchets or blanks are cut from the strips. These will later be transferred into coins by the impressing of the insignia of the government.

However, these embryo coins receive a great amount of attention ere they go to the coining presses. First of all they are cleansed of grease, and then rinsed in clean water and dried in a large copper pan, heated by stream. Next, the planchets are taken to the selecting tables, and all the perfect blanks are separated in what is known as the adjusting department of the mint. If a blank is found to be heavier than the legal requirement, the edge is filed down, but if lighter than required by law there is nothing for it but condemn the piece of metal and send it back to the smelter and refiner to be remelted.

The milling protects the surface of the coin from abrasion. In the milling machines the blanks are fed by hand into a vertical tube, and one by one are caused to rotate in a horizontal plane in a groove formed on one aide by a revolving wheel and on the other by a fixed segment of corresponding groove. Each piece, as it passes through this narrow groove, has its edge evenly forced up into a border or rim.

The melted pieces are now subjected to a further cleansing. To facilitate this cleansing, act well as to soften the pieces for imprint of the dies, they are annealed by heating to a cherry red, then dipped into a solution of sulphuric acid and water sufficiently strong to clean and brighten them. After being thoroughly rinsed in boiling water they are hand riddled in sawdust, to dry them, and are then ready for the stamping press.

The most important operation in the stamping of coins is the adjustment of the dies in the press. This adjustment requires great skill and long experience, much depending upon the character of the metal to be operated upon. The blank pieces of metal that are to be made into coins are fed to the coining press through a vertical tube and as, each piece reaches the bottom of the tube held by steel collar. Thus suspended, the blank is closed upon by the dies, which have tremendous pressure behind them, and the obverse and reverse impressions are made at the Fame time. For making sharp, clear impressions upon double eagles a pressure of 17ft Ions is employed, whereas 120 tons is sufficient to stamp the eagle, which is of course of smaller design. Double eagles and eagles are struck at the rate of eighty per minute, while half eagles and quarter eagles are struck at the rate of one hundred per minute.

With the exception of some technical details connected with the process of annealing, the operations incidental to the coinage of silver are identical with those for gold, as above described. A pressure of 150 tons is necessary to stamp a silver dollar, 119 tons for a half dollar, 80 tons for a quarter, and 40 tons for a dime. Dollars, half dollars and quarters are produced at the rate of HO per minute, while dimes are turned out at an average rate of 100 per minute. The counting of coins of all denominations is one of the important tasks at the mints. Gold coin is put up in drafts of $5,000 each. Silver coin is put up in drafts of &1,000 each. Of course, all coins of a given denomination are not identical in sine, or rather, in weight, some being heavier and others lighter than the standard weight. The government allows a limit of tolerance for fluctuation. The legal limit is one-hundredth of  an ounce in &5,000 worth of gold or two-hundredths of an ounce in &1,000 worth of silver, but as a matter of fact it is seldom that an allotment of coin approaches anywhere near this amount of variation from standard.

A strict record is dept of all precious metal handled at the mints, in order that losses in the process of manufacture may be minimized. How watchful an eye is dept on all operations connected with money making is indicated by the care exercised with regard to “sweeps,” which is a broad general term used at the mints to refer to every kind of waste material known to contain, or likely to contain, gold or silver. The floor of the melting room is swept each day, and the gatherings from the broom are thrown into one of the crucibles, so that scarcely a particle of the precious raw material is wasted.

The actual “sweeps” consist of broken crucibles and dipping cans, all ashes from fires, burnt gloves, aprons, sawdust and packages in which bullion has been sent to the mint and even the settlings in catch wells and roof gutters—in short, everything which may contain bullion without being visible to the eye. A considerable portion of the “sweeps” are sold, and at the Philadelphia mint from $18,000 to $20,000 is received every year form the sweeps produced in the melting department alone.

The prices published in this Book are these which WE PAY for the coins.


If you want a book which shows the price WE SELL COINS for, send only Ide and we will send you out 48-page illustrated selling list.

Mail Coupee on Page 204