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How to Locate Alluvial Deposits

Alluvial deposits are deposits of minerals made by water. These deposits are usually carried by rivers or deposited by floods. The mineral composition of an alluvial deposit is normally heavier minerals, including many valuable minerals and metals. Prospectors look for alluvial deposit areas in panning for gold, and mining for precious metals. The heavier nature of these materials means they're more likely to be frequently found in a given area; finer minerals are carried further away and deposited elsewhere. Locating an alluvial deposit can prove lucrative if you find precious metals.

Instructions

- 1
  Look for large concentrations of black sandy material around shores or shoals of lakes, rivers and streams. This is an indication of a mineral with a high iron oxide content, which is heavier than other minerals and is easily deposited along the shores of a body of fresh water.
- 2
  Look for coarse shiny rock in the bends of rivers, typically in natural hollows, or at the break of slope along the contour or a river or stream. These areas are prime indicators and locations of alluvial deposits.
- 3
  Search the base of waterfalls for large deposits of black, coarse or shiny minerals. These areas lock in alluvial deposits because of constant water pressure.
- 4
  Search the base of any escarpment, or at the base of mountains or canyon floors. These areas may require a bit of digging until the earth appears to change in color. Alluvial deposits in these areas are hard to spot because they are thousands of years old. If on the surface, they are typically darker in contrast to the surrounding landscape and their texture will appear extremely coarse. The area may have frequent dispersed boulders near the mountain front.

Rocks & Minerals