Treasures2much:
Welcome to DUSA.
While I do believe in some of the claims about man-made markers or "monuments" such as cairns being destroyed by Dutch searchers/prospectors and cattlemen...even maybe forestry workers who sought to limit the traffic in certain areas... I also have difficulty in understanding why anyone with a valuable mine or cache of "treasure" would construct a set of such "signposts" which could lead any observant passer-by directly to their valuables.
It seems more likely to me that most, if not all, of these probably marked routes to water or temporary food caches like this for example.
Marker spotted high on ridgeline from below.

Looked for a cache...spotted lower and to the right.

Opened each of the cans...rice in one and beans in the other two.

When I described this find to Tom Kollenborn, he said the Apache likely made the cache.
A couple of other old hands thought the same, based on my description of the contents.
Regards:SH.