danny......the groove was made by pecking at it with another rock called a hammerstone.......hammerstones are common artifacts at sites....but are often overlooked. the bit was formed by constant grinding against sandstone or other abrasive material. quite time consuming............mostly done at night around the campfire.

Here is a maul/hammer. That was a great find by your friend.

look pretty smooth to have been pecked out with another rock

after its been pecked out, its polished............some axes have different degrees of polish..........which add or detract from the value of the axe

Full grooved ax and a nice one, and yes there pecked out and then polished . most wont go in the thousands of dollars range but on a average of five to six hundred for a nice one ,like i said thats a nice one.

I used to work with some archaeologists and in the evening we would sit outside the hotel over some beers and they would knapp arrowheads out of old TV glass. They said they used it for practice and the TV glass was easy to work with. They said using chert/flint to work with was a lot more difficult and required more skill and learning curve. But, there were some good knappers out there and could make some masterpieces with just some chert rocks.

It would be interesting to know if any of the really good knappers have attempted to make one of those axe heads using the "peck and polish" method? If so, how long did it take?
Sometimes, I wonder if we do not give the ancient ones enough credit.

Yes Chancey unfortunately there being made every day ,just about every artifact known, sure makes it hard on collectors .

A few months ago I posted pictures of this stone tool I found a couple of years ago. It's made of basalt like the OP's tool appears to be made of. I don't think the "pecking" technique was used on this tool (maybe at the early stages), it appears that a lot of time was spent just grinding and polishing.
If you think about it though, if those old-timers prepared all their food during the summer and conserved their energy during the winter, they probably had a lot of time to work on tools like this.

Remember to the natives their time was their own, no boss, no mortgage, no vehicle, no TV. Evenings he could sit by the fire, work on grinding the stone into the grooved shape you see while shooting the breeze with his friends or family. If it took 100 nights, so be it. Often left on the site when they moved, to be used again next time they camped there.

That makes sense, left for the return trip. Without a pickup moving took a lot of foethought I'm sure. Even after doing it from birth.

Wow! Those are amazing pieces Waggler and Eric!

Eric, how much do some of those larger axe heads weigh?