Nokta FoRs Gold, a Gold Cube, 2 Keene Sluices and Lord only knows how many pans....not to mention a load of other gear my wife still doesn't know about!
I must admit to having zero knowledge about those big rocks, but that one seems interesting.
What I do notice is that the stone around where the holes are is not near as weathered as the rest, and the holes almost look recently drilled (past 10 years maybe?)
Have to wonder if it could have been used as some type of flagpole holder...