1930 Mercury Dime

[Coinbooks]

Not too sure about this coin, machine doubling is my best guess. Just looks good.

[occnumis2021]

pretty extreme MD like you say. probably the strongest i've seen on a merc!

imo, most likely, ejection doubling.

[MintErrors]

Kinda looks like this.. basically worthless doubling;

https://www.error-ref.com/abrasion-doubling/

A great Listing of different items:

https://www.error-ref.com/index-of-entries/

[Coinbooks]

thanks for the feedback and references.

[Ronald]

thanks for the feedback and references.

Though it is not a rare DDD, as Occnumis said above it is an “extreme” example, and to me has value as a well defined example even though it is not a treasure created by the mint but a rare visual aid tool of a machine mechanical error at the mint.