Climax in Lake County, Colorado — The American Mountains (Southwest)
The Big Shot
Photographed By Cosmos Mariner, August 28, 2017
1. The Big Shot Marker
One of the most significant technological advances in Climax Mine history was the implementation of block-cave mining in 1927. It cut the production cost of molybdenum in half, keeping the mine open (and profitable) through the grim years of the Great Depression.
”Big Shots” were the key to block-cave mining. Explosives placed at carefully-calculated locations throughout the orebody were set off all at once. The resulting fractures in the rock caused it to gradually collapse ("cave") under its own weight.
The most memorable Big Shot at Climax occurred in 1964, when more than 2,000 tons of explosives were detonated in the largest underground blast in mining history. A festive atmosphere reigned on that warm spring day. Colorado 91 was closed, and Climax employees lined the highway, enjoying picnic lunches as they watched a section of Bartlett Mountain a quarter-mile wide and 1,000 feet high collapse into the Glory Hole.
Gathering ore from the surface with excavators and haulage trucks is the mining technique of the future now that most of the orebody has been exposed, although some underground
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Erected by Climax Molybdenum Company & the Federal Highway Administration.
Topics. This historical marker is listed in these topic lists: Industry & Commerce • Notable Events. A significant historical year for this entry is 1927.
Location. 39° 22.043′ N, 106° 11.311′ W. Marker is in Climax, Colorado, in Lake County. Marker can be reached from State Highway 91, 11 miles south of Interstate 70, on the right when traveling south. Marker is located on the west side of Colorado Highway 91, at the summit of Fremont Pass, directly across from the Climax Molybdenum Mine, within a small park containing historical markers and mining exhibits. Touch for map. Marker is in this post office area: Climax CO 80429, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within walking distance of this marker. Welcome to Climax! (a few steps from this marker); Water Treatment Protects Downstream Users (a few steps from this marker); The Highest Compost Pile in the World (a few steps from this marker); Skiing on Top of the World (a few steps from this marker); More Than Just a Mine (a few steps from this marker); Top Secret (a few steps from this marker); Climax (a few steps from this marker); Life on the High Line (a few steps from this marker). Touch for a list and map of all markers in Climax.
More about this marker. Marker is a large composite plaque, mounted on a large boulder.
Related markers. Click here for a list of markers that are related to this marker. Climax Historical Park
2. Marker detail: The Big Shot, 1964
1964's Big Shot created a shock wave that measured in Golden at 2.9 on the Richter scale. It also provided valuable geological data for scientists who had placed seismic sensors across a wide area of the Rockies to measure the movement of the shock wave.
3. Marker detail: drilling and setting explosive charges by hand
Block-cave mining didn't make drilling and setting explosive charges by hand obsolete, just dramatically more productive. In 1964's Big Shot, one pound of explosives effectively broke more than 36,000 pounds of rock. That same pound of dynamite fractured only about 200 pounds with previous mining techniques.
4. Marker detail: Big Shot diagram
Fractured rock in the area above the stopes will continue to break and spall due to its own weight. This rock creates a grinding and breaking process all its own as it falls and is fed to the haulage level by the force of gravity.
The block-cave mining technique pioneered at Climax in the 1930's increased production, lowered costs and allowed Climax Mine to dominate the world molybdenum market for many years.
The block-cave mining technique pioneered at Climax in the 1930's increased production, lowered costs and allowed Climax Mine to dominate the world molybdenum market for many years.
Photographed By Cosmos Mariner, August 28, 2017
5. The Big Shot Marker (wide view)
Photographed By Cosmos Mariner, August 28, 2017
6. Climax Historical Park (entrance from Colorado Highway 91 at Fremont Pass)
Credits. This page was last revised on September 5, 2018. It was originally submitted on September 2, 2018, by Cosmos Mariner of Cape Canaveral, Florida. This page has been viewed 330 times since then and 40 times this year. Photos: 1, 2, 3, 4, 5, 6. submitted on September 3, 2018, by Cosmos Mariner of Cape Canaveral, Florida. • Andrew Ruppenstein was the editor who published this page.
