But interestingness is in the eye and mind of the beholder.
Both of those can let us down or play tricks - we can 'see' things that are not actually there, be fooled by the light, etc. Sometimes we miss things because of our prior experience. You know how it goes: somebody points something out, then you start seeing lots of them. You may start seeing banded flint now (as per other discussion). Also, once you have seen lots of something, it becomes less intertesting.
Interestingness is funny stuff!
If we were to measure interestingness, I wonder what units we might use; I propose the 'ooh'
Things that rated 0 oohs would be incredibly dull and boring. The normal scale might run from 0 to 10 oohs, but we'd have to leave the top end open because nature can always surprise us.
Just a thought.
In these specimens...
At least one of them has tiny round holes. Those are modern borings, though I can't say quite what sort of creature made them; various bivalves can do that, for instance, and sponges also.
The ear-shaped brown flint may have the remains of a 'rotten' core, which could be where a fossil sponge once was; see references to 'sponge' in Luanne's flint document.
The banded one is probably a fragment of a laminated siltstone, the bands being separate sedimentary laminae.
I mention sponge borings above.
Here are some photos and comments about them, on Jessica WInder's Blog.