Pretty sure its natural...

[gentleone444]

Or waste material but thought I'd check if anyone sees anything here.

 

[trdking]

Looks very natural to me. This type of stone often looks worked but nooooo !

 

[gentleone444]

Yep figured! It's a natural fake lol! Mother nature rules!

 

[quito]

Sure looks different than everything else around it. I give it a harder look.

 

[southfork]

Sure looks different than everything else around it. I give it a harder look.

I agree the rest of those pebbles look water worn my vote is a waste flake .

 

[uniface]

Little "expedient (quick & dirty) tool". Made in a hurry for some short-term job, used & probably tossed.