Editing Placer mining (section)

===Gold dredge===
{{main|Gold dredge}}
[[File:Natomas-6-gold dredge-1958.jpg|thumb|The Natomas No. 6 gold dredge in operation in 1958 in [[Folsom, California]]]]
Large-scale sifting of placer gold from large volumes of alluvial deposits can be done by use of mechanical dredges. These dredges were originally very large boats capable of processing massive amounts of material; however, as the gold has become increasingly depleted in the most easily accessible areas, smaller and more maneuverable dredges have become much more common.<ref name=":0" /> These smaller dredges commonly operate by sucking water and gravel up through long hoses using a pump, where the gold can then be separated using more traditional methods such as a sluice box.<ref name=":0" />
[[File:Placer Mines, worker steaming water to assist with mining operations, early 1900s - DPLA - d69dee0966eca12491731817b30ee312.jpg|left|thumb|Placer mine worker streams high pressure water to assist with mining operations in Park County, Colorado, early 1900s<ref>[https://pclha.cvlcollections.org/items/show/73 Park County Local History Digital Archive]</ref>]]