Flint tool?

[Roro500]

This item was found during a hike in Poland, near Pieskowa Skała. Just lying on the surface on an uphill part of a trail, so no metal detector was needed to find it. I was intrigued by its shape, nibble marks on the edges, and a nice spherical indentation in the middle of the smooth side.
I would be very grateful for a feedback from more experienced searchers if it can be a possible stone tool, or just a weirdly shaped natural piece of flint.

[mrmallard]

Bit of a tricky one. Pictures could be a little sharper which would help.
It looks like a frost flake that may have been turned into an expedient tool. This isn't unknown. The edge removals aren't as old as the original flake - you can see by the change in colour/patina. However, it could be agricultural "chatter" but I doubt it. The hollow is natural and can occur due to a fossil or frost fracture.
I'd certainly hang on to it until someone can have a closer look at the removals.
Just as a note, if this is now in England there may be rules to say it should have stayed in Poland (don't shoot the messenger).

[Roro500]

Many thanks for your review and thoughts. Interesting to hear that the circular indent is a natural feature. Makes sense, since it would be too perfect for hand carving. It does make for a very nice thumb rest when holding like a scraper. The area where it was found (a side slope of a limestone canyon) was likely never an agricultural area, so it is unlikely for the chipping to be from that. I attach the last of my 6 allotted pics, which should be sharper. For the first 5 I used a compression to save on the forum bandwidth.
As far as the cross-border traffic, it is still in Poland, so no laws were broken.
Thank you for sharing your expertise with me and others on this forum.

[mrmallard]

If access is available I would certainly have a search around that canyon and may be worth checking local archaeology reports