Another not sure item...

[hndmarshall]

location: West of Houston

Brazos river gravel.

 

This is an odd piece i have included pics of all sides and ends. At first it appeared lick a piece of rusted metal but its not, it has in the sun a sparkly appearance ...

 

[Harry Pristis]

A modern (relatively) sharpening stone.  Sharpen your fishhook or filet knife?  Just an impression.