saskatchwean corals? 2/3

[ottawafossil]

2/3

found these on shore of Lake Diefenbaker in Saskatchewan, Canada. looked to be eroded from sandy deposits with layers of harder iron-rich rusty strata. the fossils themselves are heavy, mineralized with iron and then rusted? corals? all the same type or different? i think this is in cretaceous age but not sure. see other 2 posts

 

these specimens are larger, very heavy. like solid iron, looks like outer textured surface mineralized and inner cavity separate - looks like central tubular structure did not mineralized (still sandy) in one pic (could scrape out with toothpick)

[ottawafossil]

update from responses to post 3/3 here: 

which identified co-occurrence with smaller (1-2cm diam, hollow, nodular) ophiomorpha (nodosa?) decapod trace burrows in late cretaceous sandy deposits from (probably) shallow marine environment of north american interior seaway (Bearpaw sea)

 

so these look to be from the same strata as the ophiomorpha trace burrows but appear different in several ways: larger (6-12” long, 3-4cm diam), not nodular, not hollow.

 

any ideas?

 

 

Edited July 22, 2022 by ottawafossil
adding updated info from responses to related post

[debivort]

To my eye they look like non-fossiliferous concretions.