The search for precious stones is a painstaking process in even the richest lands, with many miners barely ekeing out a living, but it is the thought of finding the big one that drives them on. Thus when a precious stone is purchased, one pays not just for the stone that was found, but for the labor of all those whose search was fruitless. This was perfectly summed up by Walter Houston in the Treasure of the Sierra Madre:
Why is gold worth some twenty bucks an ounce? A thousand men, say, go searchin’ for gold. After six months, one of them’s lucky…. His find represents not only his own labor, but that of 999 others, to boot. That’s 6000 months, 500 years, scramblin’ over a mountain, goin’ hungry and thirsty. An ounce of gold, mister, is worth what it is because of the human labor that went into the findin’ and the gettin’ of it.
Treasure of the Sierra Madre, 1948