i sent a mail to Karen Chin and this was her reply
Based on other specimens I have seen, your specimen does indeed look like a coprolite. Nevertheless, I can¢¢â¬¢â¢t say for sure whether it is based on the photographs. Actually, it can sometimes be difficult to determine whether suggestive-looking rocks are coprolites---even if they seem to have the right shape. Characteristics like color, shape, and size can be red herrings that might not necessarily provide useful clues that can be used to identify fossilized feces. I usually look for characteristics such as an appropriate chemical composition (especially calcium phosphate), the presence of chopped up organic materials that may be dietary residues, shape, the presence of distinctive burrows, and geological and paleontological context.
But I understand that the Speeton Formation has a subunit called the ¢¢â¬
âCoprolite Bed¢¢â¬ or ¢¢â¬
âE Bed¢¢â¬, so I suspect that numerous coprolites have been found in this Formation! You might consider contacting geologists at a local college or one of the moderators of the following website to see if they can provide more information about coprolites found in the Speeton Formation.
Associate Professor and Curator of Paleontology
Geological Sciences and Museum of Natural History
University of Colorado
Boulder, CO 80309
I have several other fossils i would like an id on will post when ive take photos of them
thx for all info