This is a large Pre-Columbian grooved polished stone hammer axe, displaying actual ancient use damage and wear on the chopping bit. It is substantial in weight and could have been used as a weapon, as well as for utilitarian purposes. This style axe was popular during Native American history throughout Central and North America so attributing it to a specific Pre-Columbian culture is not possible other than it was reportedly found in Mexico in an old U.S. collection. The butt end is rounded making this axe an effective hammer when used with the end opposing the broad chopping end. Axes like these would have made very effective fighting weapons, able to inflict devastating body damage with a single blow. They could have also been used to chop materials such as wood but narrower, polished celt axes have been known to be better in that purpose.
The ancient impacted minerals and sediment in the chip on the tip is indicative that this was ancient damage from use, not modern which would display under magnification as fresh stone crushing and breakage, as well as lacking sediment deep in microscopic crevices. NO REPAIR OR RESTORATION.