I would like to know what they are. Fish net weights seems plausible but drilling holes in rock for that purpose would be a lot of work for the payoff and risk of loss. I've long been a student and collector of native art and artifacts. Some years ago I went on a 32 day Grand Canyon expedition as a geology assistant and ornithologist sponsored by the National Geographic Society and the National Science Foundation. We stopped at points all along the Colorado River to explore caves, cliffs and canyons for various studies. Some of the valleys we explored were filled with native artifacts. Every square foot on the surface showed pottery shards and tools of bone, stone and wood. I did't collect anything other than legally permitted packrat middens there but I have seen collections of arrowheads and spear points from the paleoindians who lived and hunted along the Continental Divide near my home. There's so much yet to be learned from that area of the peoples and culture of the continent.

The recent MSM promoted sensations of metal obelisks dropped into wildland areas illustrates the importance of protecting sensitive wildland sites from the hoards of nincompoops seeking social media likes.