New Techniques For Old Mines

A good place to look for elephants is in elephant country, and old mining districts are certainly elephant country as far as minerals are concerned. In many areas probably more ore is still in the ground than has been taken out. The old timers were good miners and hard workers and when they left ore behind, it was usually for good reason; but many an old mining district has been revived by new approaches to old problems, taking advantage of new techniques and new equipment. One of these is the Front Range mineral belt of Colorado, which has produced minerals for the past 100 years through the ups and downs of mineral prices and the general economy. Gold, silver, copper, lead, and zinc have been found in abundance in the complex sulfide veins of the area. Between Idaho Springs and Central City lie several strong veins which have been mined successfully in the past. The two strongest of these veins, striking northeast-southwest, (Lake-Bald Eagle), and northwest-southeast, (Crown Point-Belman) , and dipping northeast and northwest, respectively, intersect in a flat X near the head of Virginia Canyon. From the lowest drainage of the area, Clear Creek Canyon, the old timers drove the Central, or Big Five, haulage-drainage tunnel due north. It intersects the two veins 8460 ft from the portal and 1670 ft below the surface. The two veins were mined successfully at the surface and at the tunnel level. Without an opening to the surface at the in- side end of the tunnel, ventilating became very difficult as the stopes were opened up, and mining ceased in 1929. Vertically, 1200 to 1600 ft of virgin ground remains in the veins.