Is this a error on a 2019 proof set?

Kliao

I got my proof set in from the US mint and saw there was frosting on the background of the coin. To the left. Please pitch in on What you think

Goldminers

I believe that is how they were all minted. Sort of an inside/outside look.

Ebeneezer

I believe that to be intentional, a doorway into another room. Mine is identical.

mannie gray

I had the same thought when I got mine....but..
I have seen some that look like the OP's (and mine) and some that don't , so I don't really know.

Kliao

Ok thanks for all your inputs

Hemispherical

@Kliao

Portraying a window.

From the Mint:

“This design depicts a mill girl working at a power loom with its prominent circular bobbin battery. A view of Lowell, including the Boott Mill clock tower, is seen through the window.”

Kliao

Ok thanks for your help!

grip

Maybe to give it dimension..

Kliao

Possible

ricko

That is typical of all the ones I have seen...and the set I have as well....Cheers, RickO

Kliao

Thanks for all your inputs. I just thought it was a bit weird to have frosting there