What could this be?

[Avenue]

Hi,
For anyone who can help me.
A while ago on a bike trip, i found this remarkable fossil.
However only recently after brushing off the loose sedement, i found a very small amber coloured cristal.
This makes me daubt my original guess that this might have been some sort of crushed clam.
How ever, now im starting to suspect it could also be a tree/branch.

Does anyone have an idea what this could be?

Greetz