engravings?

[Chance.D]

 

[GatorBoy]

They look natural to me.
The one farthest to the right looks different somehow.. Don't think it was engraved purposely by a Native American but might be worth a closer look to figure out how the marks got there

 

[The Grim Reaper]

Natural stones with natural fracture lines. Not engraved and not artifacts.

 

[rock]

Welcome to the site Chance. They are natural I find those lines on the Limestone rock around here even though your rocks are either quartz or sediment. Keep looking for flaked material instead of incised or ground. Start with flint and after you find that worked piece then go towards the other types. It takes some study to see what type of things ancient man made. Search the net. HH, rock

 

[Chance.D]

Thanks Rock. Will do.