85 - 55 million years ago
Faulting throughout the region creates the Santa Rita and Patagonia ranges we see today. Various intrusions also create noticable landmarks, like the granitic Elephant Rock on the western slope of the Santa Ritas. Another intrusion is Granite Mountain, about 1.5 miles from Greaterville. It is likely that gold imbedded in this granite eroded into the various local gulches to become placer gold - small particles of gold mixed in with gravel or small sands.