Weight Of US Coins

I have a 1902 that weighs 25.1 grams, it is almost worn smooth. Most weigh between 26.2 and 26.7

Don't forget that there is the accuracy of your scales to consider, the wear of the coins, the additional weight of impurities and last but not least what you were drinking prior to the weighing.
What I've always wondered is if the higher you go on Earth, the less gravity has on a coin, so shouldn't it matter where you are as to the weight of a coin?

Texasmick

Thank you for your scientific approach of this matter, as I was about to consider it, because I am 2800m above sea level, but after you have cleared it I will neglect this factor.

Anyways I still need the margin that can be considered in buying raw Morgans.

And thank you for all who have contributed to this post.

I thought thing weights different down under in Aussie. HaHa.

To give an idea on wear, a postage stamp weighs over .1 gram and a business card is 1 gram. So it is pretty easy to see how over 100+ years the coins can wear a little. I have heard that a lot of the fakes are about 24 grams and if you had a real Morgan at 24 grams you probably couldn't tell it was a Morgan.

Note there are numerous locations below sea level also. A coin would weigh more down there also. As to the top of Mount Everest, I'll be no one ever weighed a coin up there to prove anything one way or the other. Now here is something to consider. Does a coin weigh less in the ocean? A person can float much easier there so you would think a coin is also lighter there. Regarless of that, a coin can be different weights at the same location pending the atmospheric conditions. A high pressure system may push down the scale more than during a low pressure system.

From time to time I weigh coins on a gram scale accurate to .01g or better to learn more about coin wear. On uncirculated coins I have yet to find a coin that exceeded the specified weight. Usually they were a little below - in the range of -.05g. Circulated coin weight loss is variable - in general weight loss is 5% to a G grade, though weight loss seems to be related to the coin's surface area and thickness. The two highest % weight loss coins I have are a $2.5 lib in G, and an 1811 bust half in AG: around -7.5%. I think the higher % loss is due to the exceptionally low thickness of the $2.5 (and I would expect similar weight loss in a dime, though I haven't checked any), and due to the low thickness to diameter ratio on the half (I don't see weight losses this high on seated lib and later halves).

In the case of a Morgan dollar I wouldn't expect more than 5% weight loss all the way to G. Anything below 25.5g weight would be suspect. On an uncirculated dollar anything less than 26.6g, or over 26.8g, would be suspect.

I've wondered whether circulation weight loss might be some assurance of authenticity, especially on common date coins. It would be a lot of work to forge an uncirculated coin, abrade it in a way that it matched a worn coin's weight and appearance, and finally patinate it so that it looked circulated. It would be worth the effort for 1916-D dimes and 1901-S quarters, but there is little to be gained by generating another 1892-P quarter in G-VG. The only profit in faking a common coin is from using a base-metal - and all that is needed to detect these is a good scale.