After thousands of dollars in quarters for quite awhile I finally found a real error other than just the Homestead and Rushmore DDRs I come across. Was quite pleased to see this when I poured out about half of one of the rolls. Still have 18 rolls to go tomorrow. Also, is it just that Denver does a much better job making quarters than Philadelphia? I came across these 3 that I snapped with a Philly quarter. The Denvers are shiny like uncirculated proofs but I suspect they are just brand new circulation quarters. The pictures don't really show how new they look...it's getting dark and I was in a hurry. Input?
Nice Clipped Planchet. You can see the Blakesley Effect well also. There was a thread a few days ago asking What were you doing in 1977?.. to show errors from 1977. This Quarter would be great as an example! https://www.cointalk.com/threads/what-were-you-doing-in-1977.276992/ (The Denver vs. Philadelphia question.. I don't know)
Okay, I'm lost. Besides the clipped planchet (which is great) what am I looking at regarding the other quarters? Are you just comparing the Denver and Philly Mints? Because Philly is a disaster when it comes to quality control.
Some definition I found - The rim opposite the curve clip will be flat and poorly formed. This effect is known as the "Blakesley effect" and occurs due to the absence of pressure in that area during the rim upsetting process. Normally the blank rotates through the mill which becomes increasingly tighter on the opposing sides of the blank as it progresses through. This creates the pressure necessary to upset the rim. When the blank rotates to the area of the curved clip the pressure is released and the rim fails to be formed in the area opposite the curved clip.
While in the upsetting mill, there is not enough pressure in the clipped area to allow adequate metal flow on the opposite edge (far side). It's like a seesaw with people of the exact same weight on each end. If you remove one of them, the other person has no one to support the weight. Chris
I wondered if there was an explanation for the flat area directly across from the clip and now I know. Thanks!
