Dinosaur coprolites

I took far too long to do my homework on these. Reading around on the forum, it seems that these are not fossilized feces. Rather, they are likely silicate (agate and/or chalcedony) replacements of soil nodules. I didn't notice any bone fragments in either even under 20x magnification (so wouldn't have been carnivore), and there was no reaction upon application of ~1M HCl (herbivorous coprolites are typically calcareous). Since these are commonly sold as "dinosaur coprolites," I will leave this in the album as an example of what to be wary of. Luckily, I didn't pay much at all for these.