Det låter som Messiasstenen [ 1986] av Martin Caidin .
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Att stjäla från blurb:
Doug Stavers plays the mercenary game, and every time he plays he wins: in Africa, Central America, Vietnam or in the USA. Now he's on the biggest hunt of his life: to find and seize a certain object that, incredibly, confers the power of absolute belief on its owner. Christ once wore it. So did Mohammed. The last to own it was Adolf Hitler. The next will rule the world. It's code name is "The Messiah Stone"