Hobby error experts who labeled 2004-D Wisconsin extra-leaf quarters the result of random occurrences were bolstered somewhat in their case by a report of the U.S. Dept. of the Treasury Office of the Inspector General.
The report also pegged the number of extra-leaf quarters produced at up to 50,000 pieces, far higher than any previous estimate.
The fact that these reached circulation was due to a press operator at the U.S. Mint in Denver who picked a bad time to go to lunch.
While he was on break, thousands of the extra-leaf quarters were produced and bagged for shipment.
The Inspector General?s report concluded that the flaw was caused by ? ... some element of the production process outside of human control,? though the exact cause remains unknown. No criminal charges will be filed in the case, nor was anyone fired.
?We are pleased the Inspector General found no evidence of any intentional criminal conduct,? said Becky Bailey, a spokesperson for the U.S. Mint. ?We have a dedicated work force that?s takes pride in their work.?
According to the investigation report, on a Friday night in November 2004, the press operator noticed during his spot check that ?leaf up? Wisconsin quarters were being produced by one of the five presses he was responsible for.
In accordance with standard operating procedure, he shut the machine down and placed the defective coin (the report calls it a misstrike) on top of the machine, along with required documentation of the misstrike. He then took his lunch break. After returning, he realized the machine had been turned back on and was again churning out Wisconsin quarters.
The report says the press operator assumed the die had been changed, which the die setter is supposed to do when a press operator finds that a press has been producing bad coins.
At his first spot check after his break, the press operator noticed again the same misstruck coins. So he shut the machine down for a second time and consulted with his supervisor. After showing his supervisor the blemish, the die was changed and all the coins in the cash box of the press were placed into the condemn tank.
When full, the condemn tank is emptied and the coins are put into a machine that stamps them into a waffle-like pattern, leaving them unfit for circulation.
However, there was about an hour and a half between the time when the press operator first shut the press down and the second stoppage.
The press operator estimated that 35,000 to 50,000 of the bad Wisconsin quarters were produced and then shipped from the Denver Mint with good quarters. Previous estimates placed the number at about 1,000.
The report also specifically excluded clashed dies as a potential cause of the problem.
The error quarters feature an extra leaf on the left side of an ear of corn. Most were discovered in Tucson, Ariz., and near San Antonio, Texas.
As a result of this case, the Mint has taken steps to prevent future problems. In January 2005, the Denver Mint instituted a policy for collecting a ?last strike sample,? meaning a coin is produced immediately prior to the retiring of the die for checking.
More recently, the Mint has decided to retain ?first strike sample? for a longer period of time, with retention being extended from six weeks to one year. The ?first strike sample? is produced when a new die is set into a press.
The procedure for a first strike involves the press operator running the press by hand to produce one coin, which is inspected to make sure it meets certain standards. If it does, the coin is placed in an envelope, along with a standard form, that is turned over to a supervisor.
Procedure also calls for required random spot checks to be performed every 15 minutes. Press operators are not required to complete logs and documentation related to the spot checks.
According to Bailey, the Inspector General investigation into the Wisconsin quarter variety is now closed. However, there is still the matter of the second Wisconsin quarter variety, the so-called ?low-leaf? specimen. No explanation for this variety has yet been offered.
The U.S. Mint produces 15 billion coins per year. ?Over the years, we have greatly tightened our quality control and this is a highly unusual occurrence,? said Bailey.