The Australian Gold Nugget is a gold bullion coin minted by the Perth Mint. The coins have been minted in denominations of 1/20 oz, 1/10 oz, 1/4 oz, 1/2 oz, 1 oz, 2 oz, 10 oz, and 1 kg of 24 carat gold. They have legal tender status in Australia and are one of few legal tender bullion gold coins to change their design every year, another being the Chinese Gold Panda. This and their limited annual mintage may, unlike for many other bullion coins, raise their numismatic value over the value of gold used.

The Gold Nugget series was introduced in 1986 by the Gold Corporation, a company wholly owned by the government of Western Australia. This issue of coins had two unique features: a "two-tone" frosted design effect, and individual hard plastic encapsulation of each coin. These features were unusual for a standard bullion coin and gave the Nugget a unique market niche.

From 1986 to 1989, the reverse of these coins pictured various Australian gold nuggets. With the 1989 proof edition, the design was changed to feature different Kangaroos, a more world-recognized symbol of Australia. The coins are today sometimes referred to as "gold kangaroos".

In 1991, 2 oz, 10 oz, and 1 kilogram sizes were introduced. These were created with the intention of using economies of scale to keep premiums low, and are some of the largest gold coins ever minted. In 1992, the face values on these large coins were lowered to keep them proportional to the 1 oz coin. The reverse of these coins does not change annually like the lower denominations; the same "red kangaroo" design is used every year.

In October 2011, the Perth Mint created a one tonne gold coin, breaking the record for the biggest and most valuable gold coin, previously held by the Royal Canadian Mint.^[1] The coin is approximately 80 centimetres (31 in) in diameter and 12 centimetres (4.7 in) thick. It features a red kangaroo on the front of the coin and a portrait of Queen Elizabeth II on the reverse. The face value of the coin is A$1 million, but at the time of minting it was valued at over A$53 million.^[2]

The Australian Gold Nugget coins should not be mistaken for The Australian Lunar Gold Bullion coins. Both coins are minted by Perth Mint and have .9999 purity, but Lunar coins use images of different animals from the Chinese calendar instead of the kangaroo.

Specifications[link]

References[link]

External links[link]

• Australian Gold Nugget Coin Pictures

A photo of a large gold nugget from the Kuskokwim Mountains of central Alaska. 6.6 x 2.0 x 1.1 cm. Weight 77 grams

"Gold nugget" may also refer to the catfish Baryancistrus xanthellus or the mango cultivar Gold Nugget.

A gold nugget is a naturally occurring piece of native gold. Watercourses often concentrate and grow the nuggets. 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.

Formation[link]

Many nuggets are formed by cold welding of smaller particles and fragments in streams and rivers. Gold's softness makes it prone to welding under impact or hammering loads, such as those produced at waterfalls and in rapids. There is no oxide surface layer to inhibit adhesion between gold flakes. So when pieces of gold hit one another under pressure, they may join into a bigger piece.^{[citation needed][dubious – discuss]} Some nuggets may have been present in massive form in the original vein before erosion, often showing signs of abrasive polishing by stream action. (Other precious metals such as platinum form nuggets in the same way.) The exceptional ductility and malleability of gold means brittle fracture is impossible.

Composition[link]

Nuggets are usually 20K to 22K purity (83% to 92%). 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. The common impurities are silver and copper. Nuggets high in silver content constitute the alloy electrum.^[1]

Largest specimens[link]

The largest gold nugget found was the Welcome Stranger, found at Moliagul, Victoria, Australia in 1869 by John Deason and Richard Oates. It weighed gross, over 2,520 troy ounces (78 kg) and returned over 2,284 troy ounces (71.0 kg) net.^[2] It eclipsed the Welcome Nugget found eleven years earlier in Ballarat.^[3]

The largest gold nugget found using a metal detector is the Hand of Faith, weighing 875 troy ounces, found in Kingower, Victoria, Australia in 1980.

Gallery[link]

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  A large gold nugget from Nevada County, California.

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  An Alaskan gold nugget weighing 63.8 grams.

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  Alaskan gold grains.

See also[link]

• Gold mining
• Gold prospecting
• Gold rush
• Holtermann's Nugget, the largest specimen of native gold ever found. Not a true nugget.
• Latrobe nugget
• Nugget (coin)

References[link]

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