List of gold nuggets by size

Gold nuggets of various sizes have been found throughout the world. Historically, they are melted down and formed into new objects. The Welcome Stranger is the biggest alluvial gold nugget found, which had a calculated refined weight of 97.14 kilograms (3,123 ozt). Three of the biggest nuggets come from the Brazilian Serra Pelada Mine. Most of the large nuggets were melted down into ingot form and so only have historical records of their size and mass.

The Hand of Faith is the world's largest gold nugget found by using a metal detector.
A wood-engraving of the Welcome Stranger published in The Illustrated Australian News for Home Reader on 1 March 1869. The scale bar across the bottom represents 12 inches (30 cm).

Formation

A gold nugget is a naturally occurring piece of native gold. Watercourses often concentrate nuggets and finer gold in placers. Nuggets are recovered by placer mining, but they are also found in residual deposits where the gold-bearing veins or lodes are weathered. Nuggets are also found in the tailings piles of previous mining operations, especially those left by gold mining dredges.

Nuggets are gold fragments weathered out of an original lode. [1] They often show signs of abrasive polishing by stream action, and sometimes still contain inclusions of quartz or other lode matrix material. A 2007 study on Australian nuggets ruled out speculative theories of supergene formation via in-situ precipitation, cold welding of smaller particles, or bacterial concentration, since crystal structures of all of the nuggets examined proved they were originally formed at high temperature deep underground (i.e., they were of hypogene origin). [2] [3]

Nuggets are usually 20.5K to 22K purity (83% to 92% by mass). Gold nuggets in Australia often are 23K or slightly higher, while Alaskan nuggets are usually at the lower end of the spectrum. Purity can be roughly assessed by the nugget color, the richer and deeper the orange-yellow the higher the gold content. Nuggets are also referred to by their fineness, for example "865 fine" means the nugget is 865 parts per thousand in gold by mass. The common impurities are silver and copper. Nuggets high in silver content constitute the alloy electrum. [4]

Two gold nuggets are claimed as the largest in the world: the Welcome Stranger and the Canaã nugget, the latter being the largest surviving natural nugget. Considered by most authorities to be the biggest gold nugget ever found, the Welcome Stranger was found at Moliagul, Victoria, Australia in 1869 by John Deason and Richard Oates. It weighed gross, over 2,520 troy ounces (78 kg; 173 lb) and returned over 2,284 troy ounces (71.0 kg; 156.6 lb) net.[5] The Welcome Stranger is sometimes confused with the similarly named Welcome Nugget, which was found in June 1858 at Bakery Hill, Ballarat, Australia by the Red Hill Mining Company. The Welcome weighed 2,218 troy ounces (69.0 kg; 152.1 lb). It was melted down in London in November 1859.[6]

Large size nuggets are still being found around the world. On 16 January 2013, a large gold nugget was found near the city of Ballarat in Victoria, Australia by an amateur gold prospector. The Y-shaped nugget weighed slightly more than 5 kilograms (11 lb), measured around 22 cm high by 15 cm wide, and has a market value slightly below 300,000 Australian dollars, though opinions have been expressed that it could be sold for much more due to its rarity. The discovery has cast doubt on the common rumour that Victoria's goldfields were exhausted in the 19th century. [7]

List of nuggets
Name Discovered by Location of Discovery Country Date Mass Net return Notes References
Welcome Stranger John Deason and Richard Oates  Australia 1869 2,520 troy ounces (78 kg; 173 lb) 2,284 troy ounces (71.0 kg; 156.6 lb) Found only 3 cm (1.2 in) below the surface, near the base of a tree [5]
Welcome Nugget Red Hill Mining Company Bakery Hill, Ballarat  Australia June 1858 2,218 troy ounces (69.0 kg; 152.1 lb) Melted down in London in November 1859 [6]
Canaã nugget also known as the Pepita Canaa [lower-alpha 1] Serra Pelada Mine State of Para  Brazil September 13, 1983 1,955 troy ounces (60.8 kg; 134.1 lb) 1,682.5 troy ounces (52.33 kg; 115.37 lb) Largest in existence [9]
W.A. Farish, A. Wood, J. Winstead, F.N.L. Clevering and Harry Warner Sierra Buttes  United States August 1869 1,593 troy ounces (49.5 kg; 109.2 lb) Sold to R.B. Woodward for $21,637 [10]
Serra Pelada Mine State of Para  Brazil 1,506.2 troy ounces (46.85 kg; 103.28 lb) Displayed at the Banco Central Museum in Brazil [11]
Serra Pelada Mine State of Para  Brazil 1,393.3 troy ounces (43.34 kg; 95.54 lb) Displayed at the Banco Central Museum in Brazil [11]
Lady Hotham Ballarat, Victoria  Australia 1854 1,170 troy ounces (36 kg; 80 lb) 17 dwt. of gold Lady Hotham was named after the wife of the Governor, Sir Charles Hotham [12]
The Golden Eagle Jim Larcombe and son Goldfields-Esperance, Western Australia  Australia 1931 1,135 troy ounces (35.3 kg; 77.8 lb) Sold to and melted down by state government [13]
The Heron Golden Gully in the Mount Alexander goldfield  Australia 1855 1,008 troy ounces (31.4 kg; 69.1 lb) Miners found the nugget on their second day of digging [14]
Hand of Faith Kingower, Victoria  Australia 1980 875 troy ounces (27.2 kg; 60.0 lb) Found using a metal detector [15]
Fricot Nugget William Davis Sierra Nevada and Northern California goldfields  United States 1865 201 troy ounces (6.3 kg; 13.8 lb) Sold to for $3500 to Jules Fricot, who sent it to the 1878 Paris Exposition. On display at the California State Mining and Mineral Museum. [16]

See also

Bibliography

Notes

  1. The main controversy regarding this nugget is that the excavation reports suggest that the existing nugget was originally part of a nugget weighing 5,291.09 troy ounces (165 kg; 363 lb) that broke during excavations. [8]
  1. Butt et al. 2006, p. A78.
  2. phys.org 2007.
  3. Hough et al. 2007, pp. 959–964.
  4. Maclaren 1908.
  5. Kenny & Venable 2011, p. 118.
  6. Special Broadcasting Service 2019.
  7. Nolan 2013.
  8. Branco 2008, p. 608.
  9. Zorach & Phillips 2016.
  10. Chambers & Chambers 1893, p. 512.
  11. Cornejo & Bartorelli 2010.
  12. International California Mining Journal 1996, p. 16.
  13. Richards 2016, p. CH 14, Pg 1.
  14. Everist 2006, p. 219.
  15. Hill 2002, p. 222.
  16. McKowen & McKowen 2006, p. 163.

References

  • Branco, P.M. (2008). Dicionário de Mineralogia e Gemologia São Paulo, Oficina de Textos.
  • Butt, C. R. M.; Hough, R. M.; Reddy, S. M.; Verrall, M. (August–September 2006). "Origin and weathering of gold nuggets" (PDF). Geochimica et Cosmochimica Acta. Elsevier. 70 (18): A78. doi:10.1016/j.gca.2006.06.259. ISSN 0016-7037. OCLC 1570626. Retrieved August 24, 2019.
  • Chambers, William; Chambers, Robert (1893). "The History of Nugget Finding". Chamber's Journal of Popular Literature, Science and Arts. W & R Chambers. 62 (1). OCLC 5097262. Retrieved August 24, 2019.
  • Cornejo, Carlos; Bartorelli, Andrea (2010). Minerals & Precious Stones of Brazil. Solaris Cultural Publications. ISBN 9788589820080. - Total pages: 704
  • Everist, Richard (2006). The Traveller's Guide to the Goldfields: History & Natural Heritage Trails Through Central & Western Victoria. BestShot. ISBN 9780975602331. - Total pages: 320
  • Hill, Mary (2002). Gold: The California Story. University of California Press. ISBN 9780520236806. - Total pages: 306
  • Hough, R. M.; Butt, C. R. M.; Reddy, S. M.; Verrall, M. (2007). "Gold nuggets: supergene or hypogene?". Australian Journal of Earth Sciences. Taylor & Francis on behalf of the Geological Society of Australia. 54 (7): 959–964. doi:10.1080/08120090701488289. ISSN 0812-0099. OCLC 45381897.
  • International California Mining Journal (1996). "Finds". International California Mining Journal. 5. ISSN 1526-405X.
  • Kenny, Shannon L.; Venable, Shannon L. (2011). Gold: A Cultural Encyclopedia. ABC-CLIO. ISBN 9780313384301. - Total pages: 315
  • Maclaren, James Malcolm (1908). Gold: Its Geological Occurrence and Geographical Distribution. Mining Journal. - Total pages: 687
  • McKowen, Ken; McKowen, Dahlynn (2006). Best of California's Missions, Mansions, and Museums: A Behind-the-Scenes Guide to the Golden State's Historic and Cultural Treasures. Wilderness Press. ISBN 9780899973982. - Total pages: 248
  • Nolan, Pat (January 17, 2013). "Gold nugget found near Ballarat". The Courier. Retrieved August 24, 2019.
  • phys.org (October 16, 2007). "Gold nuggets reveal their inner secrets". phys.org. Retrieved August 24, 2019.
  • Richards, Jim (2016). Gold Rush. Fremantle Press. ISBN 9781925164022. - Total pages: 336
  • Special Broadcasting Service (2019). "Famous Australian Nuggets". Special Broadcasting Service. Retrieved August 24, 2019.
  • Zorach, Rebecca; Phillips, Michael W. (2016). Gold: Nature and Culture. Reaktion Books. ISBN 9781780236131. - Total pages: 224
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