All is Machine Doubling
even the face. When looking at your coin, see if the same doubling direction is on all the devices. If so it is machine directional doubling. If the the doubling is in different directions then the machine was very loose altering in more than 1-3 directions. No premium for these, but always nice to know what you are looking at. Machine Doubling
is seen on the outside and inside of devices. On a doubled die, the device show spreads in the center of the devices with sometimes notching on corners of devices. On the single squeeze dies the doubled dies are distorted in shape, that reminds me of an over inflated bicycle tubes:
Sometimes Liberty is altered:
The wider the spread in the centers of the devices, the larger these devices appear enlarged.
On Machine Doubling
the opposite happens the out edges of devices are reduced in size, flattening the contour of the normal devices on one side of the devices.
Note the MD reduces the size compared to normal devices?
On the motto area on the quarter, We have an example of machine next to a DDO
on another coin:
Note the distortion of the devices. The Machine Doubling
does not enlarge the devices, just alters them. On a doubled die, the doubling is on the die and all coins struck with that die will show the spread/distortion of the devices.
On your coin the devices are all alter in probably the same direction when you view the whole coin. On these ATB Quarters
the only area affected by a doubled die is on the centers of the devices on one side or the other. Not on the outer devices of the coin. The difference? Machine Doubling
is cause by the machine. A doubled die has the doubling on the die, thus the term doubled die. But even on a doubled die, the machine cause Machine Doubling
can be present. So if you have Machine Doubling
on a normal coin, it adds no premium for this. I there is Machine Doubling
on a doubled die, it is still a doubled die, but having Machine Doubling
. (Most variety collectors prefer not to had Machine Doubling
on their examples of doubled dies, as it is just a distraction. But when graders look at them, they accept them as doubled dies. (It is the buyer that decides if he likes it, or not? CoopHome
: How to Identify single squeeze doubled dies these coins? (The locations are different on the hub doubling.)