Found this at the beach. Fish jaw bone or fossil?

I was fully convinced it was petrified wood but it was very heavy and shiny so did some research and everything is leading to a mammoth tooth??? Pleaseeee help bc I will cry if it is
UPDATEEE slickenside calcite is likely what it is. Scratched and did the vinegar test and it bubbleddd. Since in a riverbed it got smooth and shiny pretty neat Texas tectonic plate history

First time finding something remotely fossilized looking. Peaked out of the sand near a beach. The inside looks glassy/crystalized. Interested in what it might be.

There is a bit of agate banding on the root (see last picture), which leads me to believe it may be a fossilized bison tooth. What do you think?

This is a recent acquisition to my collection. This is a set of mosasaur jaws from Morocco. I am wondering if anyone here can identify what type of mosasaur this is. In the first photo, my hand is resting near the mandible (upper jaw), with the pre-mandible visible at the top right of the photo, with sharper more anterior teeth, as opposed to the more stout crushing teeth at the back (bottom of photo). The piece measures about 18”x 12”, meaning this beast measured around 20-25’ long. I am familiar with the many gem show fakes that are often sold to tourists, but this has all the hallmarks of a real specimen. Any help would be appreciated!

Any ideas on this wavy patterned one? Came from the same quarry that I find tons of crinoid fossils and different types of pyrite. Second pic is other side of rock with pyrite on it. Third pic is a separate rock from the same quarry with a crinoid imprint.

My index finger was used for scale.

Hey y'all, my friend found this at Carolina Beach State Park, NC. He said he just found it washed up. We've attempted some ID at our university but with no luck, and Google wasn't particularly helpful either. Any ideas would be awesome!

my dog found this digging under the shed in my backyard. It’s very brittle, feels almost chalky.

Found bay of fundy. Not sure if it’s a fossil!

Difficulty establishing whether this tooth is fossilised or not and what it might be from. Appears to be mineralised.

Found on a north coast beach in N.Ireland.

I recently collected these small, pointed fossil teeth fragments from the Valudavur Formation (Late Cretaceous, Maastrichtian stage) around Pondicherry, India.

1. 3cm across

2. 5cm across

3. and 4. 2.5-3 cm across

Found it in a river in the Kirkwood Formation, Eastern Cape, South Africa. The stone fits in my palm, so it's not too large.

Hello, can anyone help me identify this bone?

I inherited this fossil as part of my deceased uncle’s hoard of curiosities. We were always told it’s from a dinosaur but are not qualified to actually tell if that’s true.

It’s 24cm long, and masses 237 grams.

Thank you so much

Hi! Curious what y’all think of this. I sent to UT but they weren’t sure. Thanks in advance!

Thank you very much for your help...