Quality control at the mint

dan1ecu

Does anyone know the procedure that the mint uses for quality control? Do they take every hundredth, thousandth, or whatever, coin and examen it? They couldn’t possibly look at every coin.

What parameters do they check? Weight? Composition? Quality of the strike?

If they find a problem, do they stop minting and check the machinery?

Dan

MrKelso

Quality control seems to have gone on Vacation, Seen here is from a fresh roll of 2003 SAE'S

Struck throught some kind of goop

WWW

Your subject line is an oxymoron.

MrKelso

nwcs

There is a great deal of quality control. And when you consider the 4+ billion products they produce per year, their achievement is even more astonishing. Most companies strive to be 3 sigma or more in compliance. That means 5/1000th of a percent of product is outside of compliance. Let's see, 4,000,000,000 * 0.0005 = 2,000,000 out of compliance. And even that number is much higher than what the mint actually lets out.

As for the procedure, it's documented in a great book on the US minting process available from the US mint. Basically at almost every stage where something can happen to the metal, the result is checked by machine and rejects are scrapped. That much escapes is a wonder, really. I have great respect for the mint's procedures.

rd5425

I know that the mint recently started having lock boxes to drop in errors that were found, because a couple years ago some of the workers were pocketing the errors especially the quarter-sac mule and selling them to dealers.