[colorshapetexture (OP)]

I trades a guy out of this in Tucson this year. It was found in the desert in Northern Arizona.

What was it used for? Heavy!

Anyone seen one like it?
 With the groove it definatly had a handle. But a lot of weight to swing in the end of a handle. No wonder it broke.

[imatfaal]

Whatever it is - it is certainly a very pleasing object!  Combination of curves and well-defined changes of curvature is really aesthetically good to the eye- looks as if it might be quite good as a tactile object as well.  That said; is it possible it could be more ceremonial or decorative than functional?

BTW - in much of Europe trading in antiquities can be illegal, even found objects; you might want to check local laws

[CliffordK]

One could imagine a stone similar to that being used in a mortar and pestle.  Perhaps grinding grains.  And may have been hand-held.

However, I don't think the polishing on  your stone looks like a paleolithic tool.

While many cultures did produce some spectacular artwork, their tools just didn't look as refined as what you have.  So, if it is "ancient", then as  Imatfaal suggests, it could have been been art or ceremonial of nature.

However, my vote is that it is a much newer object than it appears, and may be less than a couple hundred years old.

[OokieWonderslug]

I have a couple of those. That is an axe that is broken. 100% for sure.

[colorshapetexture (OP)]

The surface on the tool, because it came from the desert. Is preserved very nicley.
Guys that have looked at it have commented it looked european to it definatly didn't come from Arizona.
 After having it my hands.
It definatly didnt have a handle. The groove from top to bottom is as polished and smooth as the out side. At least when it was made. There was no reason to make the inside of that groove that smooth if you were going to put a stick on there. Very evident.
 And it fits into your left or right hand very easily.
With its smoothness and it being hand switchadle. It seems designed for a repetitive motion verticaly.
Like .. I would call it a pestal but I don't think a circular or rotational grinding action was used. Both from wear showing and feal in hand. So a grain,hemp,hide,bone pounder. With a side for rollig pin bread making action?
 The hammer end shows a definate wear patterns.  And they are even more highly polished at what would be the striking point than the main surface. So it never struck other rock. But only wood or leather. And the blows were not heavy.

So my eyes and hands are telling me it was a bone crusher. Grain grindin, nut cracker. Possible side use for pounding and processing hemp or other stranded grasses for cloth, matts, string and rope.

But for some reason for now. Grain grinder is #1 in my mind just had to be one of its main functions as maze had to be processed before it could be consumed in the dried form.
 
 So I don't think its a great war axe. Just a simple food processing device. lol Only the most impotant tool they probably had.

Besides a cook with this in their possesion would be no one to mess with.
 Remember the cook is always right.
 And you do not mess with her important cooking tools.

[OokieWonderslug]

I will have to climb up in the attic, move a ton of junk and hunt down my copy of what you have. It is identical to yours, only not broken. My father found it in WV. The reason it is so polished is how it was made. It was rubbed against another rock for a very long time to get that effect. It is how it was carved. The fact the handle notch is polished too is a product of it's making. Us Native Americans had extensive trading networks before white man came and killed us all. I have spear points from all over the country, all found in WV. I have arrowheads made from NC rhyolite, Kanawha flint, obsidian, quartz crystal, iron ore, and many other types of rock.

You have an axe. A regular, normal, everyday axe that was used until it was broken then thrown away. They work. I have used one to cut down a tree. It takes a while, but it does work.

[JimBob]

ax  (with broken fresh surface)- just go to Wikipedia

"A hand axe or biface is a stone tool with two faces typical of the lower (Acheulean) and middle Palaeolithic (Mousterian), and is the longest-used tool of human history." 

And don't count out cavemen for esthetic considerations. Beauty was a important as function. It may have been put in use with the groove unfinished but the speed at which this would wear away wooden handles would REQUIRE a smooth groove for a handle to last and the head not to fly off, killing little Crmber, the cave girl

Ookie-slug is right!!!!