I was just curious if anyone knew what the “accepted” tolerances in variations of weight for different types of U.S. pennies? E.g. steel, copper, zinc, etc. I’ve seen .10 grams for zinc and .13 grams for copper. Haven’t seen any tolerances for steel. But I’m guessing unless the steel cent is uncirculated, variances in weight would be pretty wide. Anyways, I feel like .13 and .1 differences in weight seem a little too low to be taken seriously as an error when it comes to circulated coins. Thanks.
1943 Zinc coated steel cents Weight 2.689 grams (+/- 0.13 grams) Another member of Coin Talk has a list showing the weight and tolerance for all US coins. If I can find it again, I'll post the link. (Tomorrow, as it's late here and I'm off to dreamland).
Hey, just wanted to say thanks for posting that tolerance chart. I was also wondering where you found it and if there was any more information about how often off weight coins are accidentally made and released. I have a 1983 d penny that is a decent amount above the tolerance. It’s 2.93 grams. I know there were a few 1983 coppers found and one of them actually weighed in at 2.9 and a couple at 3.0 but I’m about 99% sure it’s not a copper cent.
It happens quite often but normally within or just outside tolerance. When the sheets of metal go through the roller system to create the thickness for the required blanks, they can be rolled thicker or thinner than normal. The chart and other info like it can easily be found on the web.
Also, remember that there are differences between precious and non-precious metals. Most precious metal standards include a hard minimum value. A one-ounce silver eagle must have at least 31.1g of 0.999 silver. It could be over, it cannot be under. Non-precious metal standards are +/- ... and only apply at the 95% level. e.g. out of 100 Lincoln cents, 95% must be 2.5g +/- 0.11g (2.39 to 2.61) and 5% can be outside of those limits.