Diamonds from a lost mine in Navajo Country? Ridiculous, thought independent geologist Clayton P. Greer. Yet here before him were gem quality diamond pebbles mounted in authentic ancient Navajo silver jewelry. Now a mining promoter was offering to sponsor a secret search for the source of these diamonds. It was a tempting prospect, to roam Utah's wild deserts and remote canyon country looking for a fortune that no one suspected. Clayton and his buddy, Jerry Brooks, devise a plan. They pose as placer gold prospectors and fossil hunters, but they find themselves being stalked by a band of claim jumpers. Outwitting them, they send these rogues on wild goose chases into the desert. Then, with the aid of a daring bush pilot and a veteran river boating guide, Clay and Jerry ultimately find the source of the mysterious gems, only to encounter conflicts with rival uranium miners, government bureaucracy, and tribal politics. Get ready for a surprise ending when local residents and a willing team of Navajo Indian workers come to their aid.