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Press more productive with experienced operators

This week's edition of Coin Clinic asks, how fast could coins be struck in a screw press?

How fast could coins be struck in a screw press?


The screw press was relatively slow but with an experienced crew, mintage rates of 20 to 25 coins per minute could be sustained for short periods.
One account of the striking of gold guineas at the Tower Mint in London in 1676 contains the quote, “I saw 26 guineas impressed (struck) in the space of one minute, measured by my minute watch. The machine was fed by one man and turned by three.”

Has the U.S. Mint ever employed women to any great extent?

The Mint is currently an Equal Opportunity Employer and has had many women working for it over the years. Back in 1850 Franklin Peale employed 50 women to weigh gold coin planchets and adjust them with files. The records show that there were more than 600 applications for what was then considered “easy” work, as it was for “only” a 10-hour day. Other jobs required 12 hours of work per day.

I still don’t understand why that coin press that General Motors designed back in the 1960s wasn’t used to avert the coin shortages of that era? Anything that could strike 10,000 coins a minute ought to be in use.

The development of the roller coin press ran into several fatal flaws. While it was true that the press, by using over 100 pairs of dies, could strike 10,000 coins per minute, it was unable to sustain that speed for more than about 10 minutes at a time.

What is a “casting board?”

A casting board is an early form of the accounting system used to do mathematical reckoning. The board had a series of lines, each representing a decimal unit: 1, 10, 100, 1,000, etc. A jeton placed on the line represented the number, while one placed between the lines equaled half the value of the next higher line as 5, 50, 500, etc. By moving the jetons about it was possible to do the addition or subtraction of quite large numbers.

Were all dates punched into U.S. dies with four-digit logo punches?

The number of digits on the logo punches varied from two to four. Examination of various coins of the mid and late 1800s shows evidence of the different number of digits from the placement and style of the numbers. The use of logo punches began with either engravers Franklin Peale or Christian Gobrecht.

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