Carlin Gold Mining Company, largest open pit gold miner in the United States, and one of two large open pit gold mining companies in the Western hemisphere, is developing a new pit at its Carlin, Nevada operation. Stripping at the new pit was started in December 1975, and 21,000,000 tons of overburden, siltstone and limestone, must be removed to expose the ore. In late 1976, the upper 200 ft of overburden had been stripped and another 200 ft remained to be stripped.