The death crystal

Scientists race to reproduce a mysterious hexagonal power crystal that supplies a major city but destroys laboratories and annihilates many researchers who test it. After a catastrophic experiment, an eyewitness who watched a crystal change shape becomes the only living observer of its behavior. The survivors grapple with telemetered experiments, lethal radiations, and the moral and technical hazards of harnessing the device. The plot follows their efforts to contain and understand the phenomenon until one man ventures beyond ordinary space, suffers fatal exposure, and returns carrying a fragile, ambiguous salvage that might offer humanity a last chance.