Q: What Determines The Final Diameter Of A “Golden” Dollar?
A: For the heck of it I decided to check some of my 2007-P Adams dollars including those with a smooth edge, normal edge lettering, double edge lettering and extremely strong edge lettering to see what their diameters were and if they differed from variety to variety. I measured a dozen of each at random with digital calipers and found the averages to be as follows:
Missing Inscriptions (smooth edge) 26.4875 mm
Normal Edge Inscription 26.4841 mm
Double Edge Inscription 26.4783 mm
Heavy Edge Inscription 26.3208 mm
Image © Ken Potter 2008
Here is a 2007-P Adams Dollar w/Heavy Inscription caused by a Schuler Edge Lettering Machine that was adjusted too tight. While they range in diameter, my latest measurements of a dozen examples found that the average diameter of these coins is 26.3208 mm, which is actually just a tad larger than an unstruck planchet. A planchet that I have here found in a roll of Adams dollars measures 26.22 mm.
While one would think that the striking of the coin would be what determines the final diameter of the coin, these measurements clearly suggest that the Schuler Edge Lettering Machine is often what determines the final diameter of a coin processed as such.