Fish tooth #2?

[Darbi]

I named this topic as Fish tooth #2? because this fossil is very similar to my another fossil in a previous topic a while ago. Nobody really have any consensus on what it is and I thought it might be a fish tooth. I hope I will be lucky this time to have someone identify it for me with confidence. Located in Ellsworth county, Kansas, age of Albian, and from Kiowa Formation. It's approximately 4mm long. I know identifying specimens from Kiowa Formation can be a real pain since it's so little researched! lol...

[Darbi]

Pictures of my another similar fossil from a previous topic.

[Peat Burns]

It looks like a bit of cephalopod shell (the second photo with the iridescence) .  Let's see what others say.

[Ludwigia]

3 hours ago, Peat Burns said:

It looks like a bit of cephalopod shell (the second photo with the iridescence) .  Let's see what others say.

I was thinking the same since there appear to be remnants of nacre on it.

[Darbi]

It appears phosphatized or pyritized? There are plenty of phosphatized and pyritized fossils at the location where I found these two. I saw dozens, if not hundreds, of tiny black 'spikes' and fragments of various shapes ranging mostly from less than .5mm to 2mm long, all on just the surface of matrices and these two above were the biggest pieces I have found so far. Several small vertebrae were also found along with it and because this, I thought it might be bones, teeth, and scale fragments from the fish.

@Peat Burns and @Ludwigia, A piece of cephalopod shell with nacre? Hmm, I never thought of it that way until you both mentioned it and I am open to the possibilities. I would have to search through the paleontologist literature about cephalopod fossils from Kiowa Formation, there are not very many about it. Thank you for your inputs.