Quality control on display at the Denver Mint during Coin World tour

Mint workers get constant reminders to check the quality of the product
By , Coin World
Published : 08/11/17
Text Size

The Denver Mint continues to be one of the two largest producers of circulating U.S. coins, splitting those duties with the Philadelphia Mint.

Since the American Numismatic Association’s World’s Fair of Money was being held Aug. 1 to 5 in Denver, Coin World was afforded an opportunity to visit the production floor of the Denver Mint. Hopes to witness the Denver Mint’s production of the Uncirculated 2017-D American Liberty silver medal, the facility’s contribution to the four-piece American Liberty Four Silver Medal set that goes on sale Oct. 19, were quashed, as production of the silver medals at Denver was already completed by the time of Coin World’s Aug. 1 visit.


The fallout from the Enhanced Uncirculated Coin set release: Another column in the August 21 weekly issue of Coin World reveals that while forms of numismatic literature like fixed-price lists were meant to be fleeting, they can actually be quite useful.


Dies were being produced for Proof 2018-S coin output at the San Francisco Mint, including an obverse for a 2018-S Lincoln cent and a reverse for a 2018-S Block Island National Wildlife Refuge quarter dollar.

The Denver Mint’s die shop, installed in 1996, executes hubbing and working die production for both the Denver and San Francisco facilities after receiving master dies from the main die shop at the Philadelphia Mint. The Philadelphia Mint also produces dies and other tooling for the West Point Mint, in addition to its own needs.

Connect with Coin World:  

Sign up for our free eNewsletter
Like us on Facebook  
Follow us on Twitter

Personnel at the Denver Mint appeared to be quite quality conscious. Signs are posted in die production areas as well as coin production area with reminders of what do to do if anomalies are detected or suspected. One particularly caught our attention in the hubbing room, where a notice was posted on a hubbing press to ensure against executing a hub that would result in dies that could produce doubled die coins.

One facet of coin production on display was the full inspection of struck coins from a coinage press — in this case, Roosevelt dimes.

Every 15 minutes, a press operator would remove samples of struck coins that had exited the coinage press and dropped into a holding box. During the inspection, the press operator would use magnification on the obverse and reverse, looking for defects and metal fill problems, and also examine the reeding on the edge.

A freshly struck 2017-D Roosevelt dime was placed into an alignment gauge, obverse facing up, to position the coin. The gauge was turned over to expose the reverse to determine if the dies were aligned. The die alignment line on the gauge was expected to orient between the E and S of STATES.

Evidence of coin defects, die alignment problems or other anomalies could result in a coin press output from a current batch being condemned for later melting and metal reclamation, and the coinage press fitted with a fresh pair of dies.

Visitors to Denver should make the Denver Mint one of their scheduled stops and take the guided tour inside the facility that has produced U.S. coinage for circulation since 1906. 

You are signed in as:null
No comments yet