I have two kinds of this medal. Basic, or it it is possible to consider differences the same medal?

It looks like the same medal with an additional piece of glass (?) on the left medal. It looks like a manipulation to fake higher value.
Have you paid for the left medal a higher price?
But may I am wrong and the piece of glass is something different??

I have bought both medals under one price. I can assume, that on the left medal there is a small part of that that then became a part of this bridge. Unfortunately, I have not received any description with a medal..