Nuggets are gold fragments weathered out of an original lode. They often show signs of abrasive polishing by stream action, and sometimes still contain inclusions of quartz or other lode matrix material. 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.
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| Crystalline gold from Mina Zapata, Santa Elena de Uairen, Venezuela. Size: 3.7×1.1×0.4 cm |
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| Relative sizes of an 860 kg block of gold ore, and the 30 g of gold that can be extracted from it. Toi gold mine, Japan. |
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| Gold leaf from Harvard Mine, Jamestown, California, USA. Size 9.3×3.2× >0.1 cm |
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| Gold left behind after a pyrite cube was oxidized to hematite. Note cubic shape of cavity. |
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| Native gold nuggets |
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| "Rope gold" from Lena River, Sakha Republic, Russia. Size: 2.5×1.2×0.7 cm. |
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| This 156-troy-ounce (4.9 kg) nugget, known as the Mojave Nugget, was found by an individual prospector in the Southern California Desert using a metal detector. |
Source: Wikipedia
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