Please help! First time poster, avid fossil/artifact collector, but stumped? For years!! Please!

[ynot]

9 minutes ago, SailingAlongToo said:

To me it looks like a water worn phosphate nodule,

To Me also.

[Archie]

+1 for phosphate nodule.

[Plax]

A rock such as this found in an area of sand and loam on high ground near a water source is usually not just a rock. If it's just a rock then it was brought there by human activity. Am reminded of large or sharp rock fragments in plowed fields of sand and silt. These rocks are not possible geologically because of sorting of the pure sand and silt. Am not considering glacial or river rafted erratics here of course. I have native american "axes" found in agricultural fields with plow strikes on them. No other rocks of any size in these fields. Not saying this is definitely a relic.

[Rockwood]

Didn't quite recon a rock to be that tough to be. 

[Peat Burns]

If it's a native American artifact, my guess is that it is a pestle.