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Placer
Deposit Definitions
Placers
deposits are deposits of any heavy, resistant metals. Gold is one of the
most common. Placer gold is any gold that has been freed from solid rock
by weathering. There are several types of placer gold: 1.
Residual placers - This type of placer occurs directly at the site of
the original gold vein. As the vein erodes gold accumulates near the
surface. 2.
Eluvial placers - The material weathered from the vein has now been
carried away from the original site, usually by gravity as material
works its way down a hill. Also known as ''hillside placers''. 3.
Alluvial placers - The most common type of placer deposit. Gold that has
been deposited through the action of water. Often called ''stream
placers'' but applies to any situation where running water has deposited
the gold (or other heavy minerals). 4.
Eolian placers - Winds carry away surface sand and dust in a process
known as ''deflation''.
Heavy, resistant materials such as gold can accumulate at the surface.
This process is most common in desert areas, particularly in Australia. 5.
Beach placers - The concentration of heavy minerals by wave action. The
most famous would be the gold deposit on the beaches of Nome, Alaska. Copyright
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