Richard, I've seen artifacts like that used for 2 purposes.

Usually the more highly crafted and streamlined ones were used as a war club.

The heavier and bulkier ones were used to break open big bones and skulls for the marrow or brains they contained.

The brains were used for tanning hides. The marrow was a delicacy. Much like butter. Indians loved that.

Molɔ̀ːn Labé Skýla!