I was counting the denticles on an 1859 Indian Head cent (the main photo from Wikipedia... link here. The obverse has (unless I'm counting incorrectly) 125. I assumed the reverse had the same, but then I thought I'd better double-check. I counted 129. I was confused. I counted again. Same results. I counted a 1909-S. I got 136 obverse, 129 reverse. 1) Am I losing my mind? 2) If not, why a different number on the reverse than the obverse? 3) If not, why would the number change over the years? I can understand minor design changes, but who really notices the number of denticles?! 4) If they have changed, how many times have they changed?
I've never counted denticles, but I've heard of counting reeds on coins that have them. In contrast to these findings, the number of reeds is pretty consistent over the years. In fact, on Morgan dollars, the number of reeds is one indicator of proof vs business strike.
In some cases, reed counts can aid in authentication. I have heard of some advanced numismatists counting denticals - I believe on seated coinage. On worn coins the denticles usually disappear before the reeding. As far as the project for the blind, I seriously doubt that any human could tell the number of denticles on a coin by touch.
@Insider, I agree that it would not be useful for identification of denomination. It is simply another metric that some people (visually-impaired or not) might find interesting, that's all.
I suspect that the design itself may have a lot to do with the numbers. Not aesthetics but type of material and amount needed in that area to achieve a full strike. Sometimes a slight change can render big results not only to the coins aesthetics, but also the life of the dies. I haven't counted them, and am guessing here, but there may be a difference in the numbers for copper nickle v.s. bronze, for that reason.
IMO, the denticals, beads, and pretty little things found on/next to/near a coin's rim have nothing to do with the life of the dies. The rim helps protect the design and and the embellishments are only placed there for aesthetics. Of course the circumference of the coin determines how many of these "artistic things" will fit. Also, as the OP has found, there are differences. I'll bet some advanced specialist collector or perhaps a TPGS professional authenticator has studied this.
They are placed there for aesthetics, but there has to be enough material in that area to support them. I know there have been design changes to original designs because a full strike couldn't be achieved where the obverse and reverse designs overlapped and required more material in one spot. To achieve a full strike, the pressure of the strike had to be raised which in turn caused premature failure of the dies. Edit to add: a good example is the 1921/22 Peace Dollar.
Or camels passing through the eye of a needle.........You guys are really that anal? I'm happy if I can count ten toes..........yup, they're still there.
It's really what is sometimes needed. Winston Churchill would most heartedly agree........if he were still here with us.
