Don't come across many of these nowadays....the horn core on the left has disintegrated due to being exposed for some time. The rest of the Buff head was buried in a creek bank.
If your interested, you might wanna consider having it dated. Had a buddy in cedar city find one about 18 years ago about the same way you found yours, anyway he had it dated and it ended up being around 2000 years old, sold it to a museum for 10k.
My friends elderly father has a buffalo skull with an arrowhead embedded right between the eyes. He was raised on a ranch and got it as a kid from an elderly neighbor rancher who found it years before in the side of a streambed. Gotta be worth a few bucks...