The area directly above the mintmark is, for lack of a better term, "incuse", isn't it? I'm not so sure you're calling this one correctly...
I know, right now I'll call it a chip . If it's measures 4 square millimeters then it this http://www.error-ref.com/freestanding-interior-internal-die-breaks/
It's not incuse. It's raised to about the same height as the MM. Here is an angled picture. Hope this shows correctly. Thanks.