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Article: Placer.(A Word to the Wise)
- Article from:
- Rocks & Minerals
- Article date:
- March 1, 2004
- Author:
CopyrightCOPYRIGHT 2004 Heldref Publications. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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As noted in previous discussions of hypogene, supergene, and hydrothermal deposits, water plays an intimate role in the formation of many types of minerals and mineral deposits in Earth's crust. The involvement of water in some mineral deposits, however, is solely as an agent of transport and segregation of minerals that have been weathered out of the rock in which they originally formed. An important example of this is the placer deposit.
Flowing water has the ability to separate transported particles based on their weight. The maximum particle weight that a current can transport depends on its velocity; thus, as current velocities increase so does the maximum ...