Native American plow?

[Ramswin]

This is being offered at a auction this afternoon.
It is described as a Native American plow.
What should I look for to determine if it is indeed what they say it is?
Also what would be a reasonable bid were it to be the real thing?
Thanks for any help offered.

 

[Icewing]

Indian Steve hit the nail right on the head, Native Americans did not have horses to pull plows prior to the arrival of the Spaniards.
Let's just say hypothetically someone were to attempt using such a stone as a plow; What would happen when it hits a big rock in the ground? It would snap off and make waste of all the effort spent shaping it.
In this case I think you had better demand the auction prove their claim, or remove their claim.
At best it might have been used as an anchor, in my opinion, but even that is speculative.
So buyer beware, it's a rock unless proven otherwise, but even rocks are not always worthless when they are unique.