Spiral Jetty is an earthwork made in 1970 by American sculptor Robert Smithson.
The 15-foot-wide (4.6 m) counterclockwise coil spirals into the northeastern shore of the Great Salt Lake near Rozel Point. It's constructed entirely of mud, salt crystals, and basalt rocks.
The water level of the lake varies with precipitation in the mountains surrounding the area, revealing the jetty in times of drought and submerging it during times of normal precipitation.
Originally black basalt rock against ruddy water, Spiral Jetty is now largely white against pink due to salt encrustation.
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