Nodule with embedded object (is it a fossil or mineral accretion?)

[Gramps]

All,

I wonder if someone may have an opinion about the object(s) in the small nodule shown here? The entire nodule is about 0.63 inch wide x 0.75 inch long x 0.5 inch thick (1.6 cm x 1.9 cm x 1.3 cm). It came from an area of shale that is likely of Pennsylvanian age in Northeastern Oklahoma. The shale from this location has many fossil marine invertebrates. I'm assuming its a mineral formation, but any thoughts would be appreciated. It is very hard to get the 3-D relief to show up in photos, so several angles and lighting conditions are shown.

Best wishes.

 

[Gramps]

Here are some photos from the side