Cripple Creek & Victor Gold Mine

The Cripple Creek & Victor Gold Mine, formerly and historically the Cresson Mine, is an active gold mine located near the town of Victor, in the Cripple Creek mining district in the US state of Colorado. The richest gold mine in Colorado history,[1] it is the only remaining significant producer of gold in the state, and produced 322,000 troy ounces of gold in 2019, and reported 3.45 million troy ounces of Proven and Probable Reserves as at December 31, 2019.[2][3][4][5] It was owned and operated by AngloGold Ashanti through its subsidiary, the Cripple Creek & Victor Gold Mining Company (CC&V), until 2015, when it sold the mine to Newmont Mining Corporation.[6][7][8][9]

Cripple Creek & Victor
Cripple Creek & Victor open-pit
Location
Cripple Creek & Victor Gold Mine
Location in Colorado
LocationTeller County,
near Cripple Creek and Victor
StateColorado
CountryUnited States
Coordinates38°43′38″N 105°08′40″W
Production
ProductsGold
Production322,000 troy ounces
Financial year2019
TypeOpen pit (ex-underground)
Greatest depth2,750 ft (840 m)
History
Discovered1890
Opened1892
Owner
CompanyNewmont Corporation
WebsiteCripple Creek & Victor website
Year of acquisition2015

The mine is an open pit operation. The gold is recovered from the ore by heap leaching. CC&V's heap leach pad is one of the biggest in the world.[10]

The mine has a visitor center[11] with displays about modern mining procedures, historical photos, ore and core samples, and mineral uses.[12] Visitors can tour the mine with advance reservation through the Victor Lowell Thomas Museum in Victor, Colorado.[13]

Geology

The ore is in altered and brecciated volcanic and volcanoclastic rocks of Oligocene age and predominantly quartz latite composition. The Cripple Creek volcanic complex is surrounded by Precambrian gneiss, granite, and quartz monzonite. The gold occurs as disseminated micrometre-size free gold and as gold-silver tellurides, or telluride minerals. Gangue minerals include pyrite, quartz, and fluorite.

History

Gold mining in the district begun in the 1890s, mostly as underground operations, chasing high grade veins. Over 23 million ounces of gold have been recovered from the district since 1890.[8] At 2012 prices ($1600 per troy ounce [14]), this would be worth around US$37 billion.

Warren, Harry & Frank Woods entered the Victor mining scene in when they purchased the Mount Rosa Placer and incorporated the Mt. Rosa Mining, Milling and Land Company on January 9, 1892. This would later become known as the Cripple Creek & Victor Gold Mine.[15]

Most of the Cripple Creek properties were consolidated into the Golden Cycle Mining and Reduction Company, and the Carlton Tunnel was completed in 1941. This 6.5 mile long tunnel drained the district down to 3,000 feet. The roasting-cyanidation Carlton Mill opened in March 1951. This mill also tested the first carbon adsorption-desorption process.[16]:110–111,113

The Cripple Creek and Victor Narrow Gauge Railroad was opened in 1967 and continues to serve as a tourist attraction.[17]

The current open cut operation dates back to 1995.[8] The operation became part of AngloGold in March 1999, when the company acquired the Independence Mining Company and thereby 66% of the mine. AngloGold merged with junior partner Golden Cycle Gold Corporation in 2008 and thereby acquired the remaining 33% of the project.[10][18]

The mine is a low-cost, low-yield open pit operation, with grades well below one gram of gold per tonne of ore. In recent years, 2008 and 2009, the mine accounted for 5% of AngloGold Ashanti's worldwide production. It is the company's only active operation in the United States.[10] In 2008, the State of Colorado and Teller County granted the mine a mine-life extension.[19]

Production and grade of the mine have steadily declined over the last few years, while the total production costs have risen from US$372 an ounce in 2007 to US$475 in 2009. The mine employed 562 people in 2009, of which 367 were permanent employees.[19]

In August 2015, the mine was sold to Newmont Mining Corporation.[7]

Cresson Vug

On 24 November 1914, Dick Roelofs was supervising the exploration of the mine to the 1300 level, when a large gold-filled vug was blasted open on the 1200 level. The next day, Roelof, a mine owner and an attorney explored the "cave of sparkling jewels". The vug measured 14 feet wide, 23 feet long, 36 feet high, which took a month to empty, and yielded 60,000 troy ounces of gold.[16]:78–80

Two "Aladdin's caves of gold" were discovered in August 1953, on the 3100 foot level of Ajax Mine, Battle Mountain. Sylvanite and Calaverite covered the walls. Mine superintendent M.H. Grice stated, "It is a sight a mining man may see but once in a lifetime..."[16]:114

Production
Town of Cripple Creek and CC&V (Cresson) Mine, 2012
High-grade Calaverite (gold telluride) ore from the Cresson mine. Specimen size 2.6 x 2.1 x 1.1 cm. Individual calaverite crystals up to 9 mm, in frosted grey quartz.

Past production figures since 1995 were:

Year Production Grade Cost per ounce
1995 76,587 ounces
1996 174,600 ounces
1997 228,164 ounces
1998 230,300 ounces
1999 231,000 ounces
2000 248,000 ounces
2001 214,010 ounces
2002 224,988 ounces
2003 [20] 283,866 ounces 0.67 g/t US$ 199
2004 [20] 329,030 ounces 0.61 g/t US$220
2005 [20] 329,625 ounces 0.62 g/t US$230
2006 [21] 283,486 ounces 0.54 g/t US$248
2007 [22] 282,000 ounces 0.53 g/t US$269
2008 [22] 258,000 ounces 0.49 g/t US$309
2009 [22] 218,000 ounces 0.46 g/t US$376
2010 235,000 ounces
  • At the bottom of the Cresson Pipe pit. The pipe is a phonolite. Notice the dike in the middle.
  • Looking into the Cresson Pipe pit. Notice the leach pile on the upper right.
  • Approximately 250 tons being unloaded into the crusher.
  • Looking into the Fuller-Traylor NT Gyratory Crusher, which reduces the ore to fragments of 3/4 of an inch or less. The mine also employs an Excel MP Cone Crusher.
  • Historic shafts reached depths of 3000 feet. However, today, the mine strictly uses surface mining.
  • Geophysical exploration for old stopes. Notice the stope tunnel on the next bench up, and in the middle.
  • A new leaching pad being constructed where the ore will be leached in 100 feet layers, extracting the silver-gold-telluride from the mostly lamprophyre diatreme breccias.
  • Milling facility for extracting higher grade ores.
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See also

References
  1. Noel, Thomas J. (2015). Colorado: A Historical Atlas. University of Oklahoma Press. p. 109. ISBN 9780806153537. Retrieved 25 February 2020.
  2. "2017 Annual Report and Form 10-K" (pdf). Greenwood Village, Colorado: Newmont Mining Corporation. 22 February 2018. p. 31. Retrieved 24 May 2018.
  3. "Annual report pursuant to section 13 or 15(d) of the Securities Exchange Act of 1934 for the fiscal year ended December 31, 2019" (PDF). Greenwood Village, Colorado: Newmont Corporation. 20 February 2020. p. 35. Retrieved 25 February 2020.
  4. Active Mines in Colorado Archived 2011-05-21 at the Wayback Machine Colorado Geological Survey website, accessed: 6 July 2010
  5. FACTS ABOUT COLORADO MINING Archived 2010-06-22 at the Wayback Machine Colorado Mining Association website, accessed: 6 July 2010
  6. "Newmont to acquire CC&V mine from Anglogold Ashanti," Engineering & Mining Journal, July 2015 p.4
  7. Newmont completes purchase of Cripple Creek & Victor gold mine, accessed: 9 August 2015
  8. About CC&V Archived 2010-05-22 at the Wayback Machine Cripple Creek & Victor Gold Mining Company website, accessed: 5 July 2010
  9. "Newmont to acquire CC&V mine from Anglogold Ashanti," Engineering & Mining Journal, July 2015 p.4.
  10. United States 2008 AngloGold Ashanti country report, accessed: 5 July 2010
  11. "Contact Us". Cripple Creek & Victor Gold Mining Company. Archived from the original on 5 December 2014. Retrieved 27 November 2014.
  12. "Cripple Creek & Victor Visitor Center". Visit Cripple Creek. Archived from the original on 5 December 2014. Retrieved 27 November 2014.
  13. "Tour the Current-day Cresson Mine". Victor, Colorado. Retrieved 27 November 2014.
  14. Gold price
  15. "City of Victor, Colorado - History". City of Victor, Colorado. Retrieved 10/4/2011. Check date values in: |accessdate= (help)
  16. Voynick, S.M., 1992, Colorado Gold, Missoula: Mountain Press Publishing Company, ISBN 0878424555
  17. "History". Cripple Creek and Victor Narrow Gauge Railroad. Retrieved 10 March 2020.
  18. US gold operation’s life-of-mine extended miningweekly.com, published: 2 December 2002, accessed: 6 July 2010
  19. United States of America: Cripple Creek & Victor Archived 2011-09-12 at the Wayback Machine AngloGold Ashanti website, accessed: 11 July 2010
  20. Annual Report 2005 Archived 2011-07-19 at the Wayback Machine AngloGold Ashanti website, accessed: 11 July 2010
  21. Annual Report 2006 Archived 2011-07-07 at the Wayback Machine AngloGold Ashanti website, accessed: 11 July 2010
  22. Annual Report 2009 Archived September 12, 2011, at the Wayback Machine AngloGold Ashanti website, accessed: 9 May 2010

Further reading
  • Cross, W., and Penrose, R.A.F., 1895, Geology and Mining Industries of the Cripple Creek District, Colorado, USGS, Washington: Government Printing Office
  • Lindgren, W., and Ransome, F.L., 1904, Geological Resurvey of the Cripple Creek District, Colorado, USGS Bulleting No. 254, Washington: Government Printing Office
  • Lindgren, W., and Ransome, F.L., 1906, Geology and Gold Deposits of the Cripple Creek District, COlorado, USGS Professional Paper No. 54, Washington: Government Printing Office
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