This is perhaps one of the most intriguing and exciting of the tons of treasures I've studied.
This account begins with a bandit with the badass name, "Hualapai Joe" Desredo.
In 1880, a stagecoach carrying 3000 oz of gold bars and mined nuggets (today that would be worth around $14,000,000). Under the seat there was reinforced iron to carry the load. It took six men to lift the strongbox into its position. There were also 2 bags of nuggets and loose gold hidden between the strongbox and the wall. It was headed from Beale Springs headed to Needles, California and about two miles west of Kingman, Arizona. (Studying archived maps of old stagecoach paths, this route should be easy to find)
Three bandits who had just robbed a store in Mineral Park saw the stagecoach leave Beale Springs and decide to trail it. The desperados robbed the stagecoach and took the strongbox. Finding it was way too heavy to get away with, they pushed it to the side of the road and covered it with dirt. They allowed the stagecoach to continue on in the dark.
The posse caught up with the men and killed them. Hualapai Joe, as he was dying, explained what they had done and said that, as the stagecoach returned on its journey in the dark, he heard crashing and screaming and suspected they went off the road.
In my own evaluation of this case, I believe the stagecoach would have crashed into a curve in the road in the dark. That the bandit heard the sounds means that the strongbox should be within hearing distance of the stagecoach crash.
Sixty years later in 1940, an historian named Maurice Kildare was approached by a Mohave County man named Max Bordon, a hermit that lived in the Black Mountain area. He claimed he ran into the old crashed stagecoach. He said it had been swallowed up by a large fissure at the edge of a deep wash.
Part of the coach and some bones within were still there, but the rest had been washed away.
(Arizona Highways magazine in 1994 carried this map above and Mohave Museum of History and the Arts carries this magazine copy to read)
Bordon took the historian, Maurice, to the location and vowed to keep it secret. WWII broke out and Bordon was killed. Maurice told a Mohave sheriff who wasn't interested. And, so, Maurice kept the knowledge until his death. He said at one point he couldn't find the location again.
So, does this strongbox still sit out there today?
Google Earth might be an aid in looking for fissures near washes along the path. Finding the bits of the stagecoach is perhaps the best way to backtrack to where the strongbox still sits.
Warning: Treasure hunting, especially in the Arizona desert, is a dangerous prospect.