The landmark Sheep bridge in Tonto National Forest - named after a now collapsed structure which was used to transporte the animals across the Horseshoe River - is a already known location for agates, however considered to be extinguished. Jeffrey Anderson found a nearby, but difficult to reach new reference for the famous 'Sagenitic agates"(pseudomorphic formations after acicular minerals) together with a friend. Jeffrey Anderson is describing this location on his website dwarve´s earth treasures:

“... Patrick Thomas and I stumbled upon apparent virgin grounds where the agates are littered all over as if they haven't been picked for millenias and it was qutie a thrill to just sit down and pick out best pieces. That gave me an idea of what it's like to experience the "Rockhounder's Golden Days"(1960s-1970s). At first glance, the agates are white as a result of so many years of bleaching by sunlight, and hidden within the agates are red, orange, yellow, lavendar and especially characteristic purple color. The agates are generally hollow with calcite inclusions which tend to be weathered away leaving behind incomplete specimens. ..."