Why can't this be a double
d die? Because the double
d die listings are only on the central areas of the designs. These single squeezed dies affects the central areas of the dies. These devices are incuse on the coin. (meaning that the devices are raised on the die) So the slightest machine movement alters these incuse devices. I did a check on 100 of these quarters, and 70% of these quarters show slight/mild/med/extreme
Machine Doubling. A double
d die is created on a coin showing hub doubling on the die.
Machine Doubling is caused by post strike machine movement. So you can have a doubled die with
Machine Doubling, but
Machine Doubling never creates a doubled die. It alters the coin post strike. Interesting point about these incuse devices. When they are more towards the center of the design, you can see how the
Machine Doubling enlarges the devices:

Note the three images:
Top:
Machine Doubling on the incuse devices
Middle: Normal stike on the incuse devices
Bottom: A doubled die on the incuse devices that makes the devices smaller than normal.
So if this was closer to the center of the design, the doubled die would be raised/duplicated if it was a raised device. Reduced, it were a raised device. But on incuse devices, the opposite happens. The
Machine Doubling enlarges the devices, and hub doubling reduces the devices. But this can never happen on the quarter devices, as the single squeeze dies only show hub doubling on the central devices. On the obverse devices, the doubled dies will show on the earlobe and on the Motto devices:
Raised devices on the earlobe:
Note the raised areas on the fields and the earlobe. They are enlarged on raised devices.
More raised devices:
Note the distortion of the devices on the right image? That is the way the doubled dies will look on the single squeeze devices. (Distortion on raised devices)
How can I prove all of this? It took seeing a 2013
DDR cent to help me grasp this concept:
http://www.varietyvista.com/01e%20L...3PDDR001.htmNote on this
DDR, the devices are enlarged on the raised devices:







reduced in size on the incuse devices:



The raised an incuse devices on the die shows up differently on the coins struck these dies. Thus the distortion sources are also opposite. That is what you are seeing on your quarter. The DDRs don't happen on that area. They are in the central areas on these post 1999 quarters.
CoopHome:
Raised and incuse devices differences on the single squeeze dies. different locations for the doubled dies and
Machine Doubling rules on the newer coins with the single squeeze die coins. how to tell the differences?