The Crystal Underground

When Ren Boissevain is not turning motorists’ heads in the bumpy-surfaced car he calls his rockmobile or guiding tourists through the cave beneath his shop, he can usually be found down some South American mine shaft in search of rare crystals.

“Crystals are my world,” says the former agate miner, showing a visitor through the glittering galleries in the artificial cave—complete with polyurethane stalactites and stalagmites—he’s made in the basement of the store.

Called, oddly enough, Crystal Caves, it holds some 600 crystals and fossils, many of which the Dutch-born 69-year-old gathered on expeditions to Mexico and Brazil. His obsession has brought its share of trouble. He’s had life-threatening encounters with con men in silver mines—one tried to throw him down a shaft, he says. And not long ago, he was robbed. It’s little consolation to Boissevain that the burglars evidently mistook his fake diamonds for the real thing. “They mustn’t be very smart,” he says mournfully.