What is this?

[Burke_Family]

Hi - we have another curious find, hoping someone here can give us some insight on what this is. We initially picked it up thinking it was a small piece of petrified wood. But upon closer inspection it looks to maybe be bone or septarian or ? The dark outer layer has a reptile-like pattern on the top side, and a smoother (more weathered?) appearance on the underside. I’ve attached a bunch of photos hoping they will help. This was found on a beach in southern Oregon. It’s about 3cm x 5 cm. Thanks… 

 

[supertramp]

Ferromanganese crust on a pebble is a possibility.

Edited April 25, 2022 by supertramp

[Mark Kmiecik]

Reptile skin is covered in scales. Google it.

[Burke_Family]

Thanks for the suggestion…. ferromanganese crust does look similar. That was helpful, thank you.   We’re still not sure what we’ve got here but the family is enjoying learning about the possibilities. 

[Mahnmut]

Hi,

I think that this is flint or chert with a lot of percussion marks, each "ring" representing one hit by another pebble in the stream or on the beach producing a cone shaped  little shockwave in the stone. Not a fossil in the sense of biological remnant, and not an artifact, but a nice piece of natural history anyway.

I am not sure if the term percussion mark in English only refers to artificial hits, like most search results that I got for it, but what I mean are marks produced by natural forces.

Best Regards,

J

[JohnJ]

13 minutes ago, Mahnmut said:

but what I mean are marks produced by natural forces.

Conchoidal fractures.