Why More Errors/Varieties From Philadelphia?

It could be a feature of the dies. Perhaps there is a difference in the final preparation. I thought I remembered reading that the mints would plate or otherwise prepare the die surfaces to harden them and extend striking life. One thing that I can state confidently is that Denver nickels have a specific surface deterioration pattern that is different from Philly. They are much more likely to develop the melted butter ghosts on lettering—especially reverse lettering—that moves towards the center. I have sometimes wondered if Denver just runs the dies longer, but that would not explain the visibly burnished (D) vs. matte (P) appearance of the nickel surfaces.

However, it is also possible that there are minor differences in planchet preparation between Philly and Denver. I do not recall anyone mentioning the visible difference on other denominations. I will retrieve a few specimens from my weekly CRH that show the pattern.

Another great article, Pete. Thank you!

I have not paid as much attention to the surfaces as I have the devices between the two mints. I have noticed that on the Denver later memorials and also the shield cents appear to have a softness to all the devices that make them look thicker, almost as if they have a slight spread.

Denver notably has had some visible planchet differences to Philly over the years. Nickels from 2000 are notable for a polished gleam. Folks here (including myself) have posted a number of mirror finished Denver coins over the past few years. I had assumed that was a planchet difference, but I've never read a pro confirmation or refutation of that observation.

Picked this one off the pile. 2022-D nickel, you can see that melted butter beginning atop FIVE CENTS. The softness and fine radial flow is visible from the center. That frosted look under magnification usually correlated to a gleaming luster on modern Denver nickels that is visibly different than Philadelphia struck coins.

A study of Hertzian Contact Theory leads me to suspect that:

The article states a faulty syllogism that since the mint experienced die breakage and shorter die life using flat dies and in 1836 converted to spherical die faces thus extending die life, therefore Philadelphia, since they experience more die events, must have flatter dies than Denver.

I hope to have more data to work with to resolve that question when I complete my analysis from additional scans I have scheduled for the end of the month.

I wonder if a different curvature would explain why Denver dies have such a specific and different deterioration pattern than Philadelphia.

It doesn't seem likely that they have different curvatures between the mint locations in the 21st century. But I suppose that many things are possible?