National Geographic : 1942 Apr
Staff Photographer Willard R,Culver From a Single Mountain High in the Colorado Rockies Comes Most of the World's Steel-toughening Molybdenum "Glory holes" in the peak at left have been formed by blasting away its heart. Beyond the company town a tunnel penetrates themountain and probes itsthick core of granite veined with molybdenite. "Blocks" of ore above are blasted down by heavy charges of dynamite. Mine and oremill (right) have long been running at top speed, for "moly" makes steel tougher and increasingly is replacing that hard-to-get metal, tungsten (p.481).