I believe you are referring to “alluvial gold,” which is gold that has been eroded from its original source and deposited by water in a new location, typically in river beds or sedimentary deposits. Alluvial gold is often found in small particles or nuggets and can be extracted through a variety of methods, including panning, sluicing, and dredging.

To extract alluvial gold through panning, a miner typically fills a shallow pan with sediment from a riverbed or stream and then swirls the water and sediment mixture around. As the lighter materials are washed away, the heavier gold particles settle to the bottom of the pan. The miner can then carefully remove the gold particles from the pan.

Sluicing involves the use of a series of boxes or troughs with riffles, or grooves, that trap the gold particles as the sediment and water are washed through the system. Dredging involves the use of a suction pump to remove sediment and gravel from a riverbed or stream, which is then processed to extract any alluvial gold present.

It’s important to note that extracting alluvial gold can have environmental impacts, such as disrupting natural habitats and waterways, and should be done in a responsible and sustainable manner.