Peerless67:
I wouldn't say "all." Are you referring to Emile C. Schurmacher's Lost Treasures and How to Find Them! (New York: 1968)?
Most of the "treasure magazine" yarns are a good deal older than that.
The late Bill Hanks, a first-rate treasure hunter and book collector (and a gentleman of the old school) once told me that in his opinion that book had one of the first accounts of the Four Corners "Gold Act" Cache (the "17 Tons of Gold" story). That is a very interesting comment on several levels...
Good luck to all,
~The Old Bookaroo