The mouth looks a lot like the 1953 half dimes without arrows that are on the PCGS website. Does anyone know if there are any other differences between the coins other than weight? I just weighed it and it came out to 1.27 grams which is more than it should weigh. I verified accuracy with other coins and if anything, the scale seems to be a little on the low side. Ex: 2011 Roosevelt dime weighed in at 2.26 grams instead of the 2.268/2.27 that it should've weighed. Also, the left arrow looks short to me....
The tolerance on the "arrows" half dimes is +/- 0.032g, so yours seems to be within specs. 1.244 +/- 0.032 =1.276-1.212 grams The modern clad dime is 2.268 +/- 0.09 or 2.35- 2.178, so I think you mistyped the weight of your "2.6" dime Jim
