Prospecting Equipment

Prospecting Equipment

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This section features types, description, use, tips, etc. on prospecting equipment. The emphasis is on showing the equipment actually in use by DGD members with discussions of their use in a desert environment. Members of the club use a wide variety of equipment. You can learn a lot by attending the monthly outings and observing the equipment in use. Club members are usually very good at answering questions about their equipment. Almost every type of gold placer equipment can be seen at the outings, even dredges occasionally though there is seldom enough water for their use. All mechanical gold equipment use some form of gravity separation which depend on the fact that gold has a higher specific gravity than most other minerals (see Gold Facts for more details). Some sections have links that provide more detailed information. For additional information, as well as plans for building some of the equipment, see the references section in the menu below.


Contents

 Sluice boxes Long Tom Dredges Recirculating Equipment Basic Tools Gold Pans Classifiers Dry Washers Vac-Pacs Rotapan Rockers High Bankers Trommels Gold Wheels Metal Detectors References Dealers/Manufacturers

 

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Sluice Boxes

The simple sluice box is not used much in the desert since these are placed in a stream with running water. However these form an integral part of other equipment such as rockers, high bankers and dry washers. The material to be run is usually passed through a classifier before putting it in the sluice. The type, size, shape, angle and spacing of the riffles depend on the usage and manufacturer. There has been some research into riffle design, for instance “An Analysis of Sluicebox Riffle Performance”, 1990 – by R. Clarkson, P. Eng. – New Era Engineering Corp., can be downloaded from the Yukon Geological Survey Publications page or ordered as a reprint. Several other publications are also available for download.

Long Tom

Also called a Broad Tom , this is a modified sluice box. In its simplest form, it consists of two sections. The upper section, called a tom, is a long trough in which the dirt is placed and acts as a large hopper. At the down slope end is a grating or screen set at a 45 degree angle. The second section is a riffle box, with the upper end set under the lower end of the tom. This receives the classified dirt that passes the screen on the tom. While water is directed into the upper end of the tom, the dirt is worked with a rake to break up any lumps of clay, clean off organic matter and knock any dirt from the rocks. The fine material flows through the screen and into the riffle box. This is usually a two or three man operation. This type of equipment is little used these days, especially in the desert, and is not used by club members.

Dredges

Keene Dredge
David Snow doing a bit of dredging at Wishful Thinking.

A dredge is basically a suction hose powered by a pump and attached to a sluice box, usually floating on a tube or pontoons. The suction hose acts like a large vacuum cleaner to extract material from the bottom of a stream or pond and deliver it to a sluice box usually floating on the surface of the water. This makes it much more efficient than other methods as one can have a continuous stream of material being worked. Several sizes are produced from 1 1/2 or 2 inch to 8 inch with the smaller ones also produced as a backpack unit, the size referring to the diameter of the suction hose. The Rocker Box has a good description and information on dredging at what is Dredging?, especially as concerns state laws.

The Schmidt Gold Trap (nicknamed the BAZOOKA) is a new and different type of dredge that looks interesting. It is shaped like a bazooka and does not use a sluice box and riffle tray. It is also lighter than a conventional dredge. See The Gold Trap & Schmidt Enterprises’ Bazookafor more information.

Dredges will process the most material of all methods but need lots of running water so find less use in desert areas. Occasionally an earthen dam is constructed and when the impound area has filled with water during a rainy spell, a dredge can be profitably worked. Owned and used by a few members but not seen much at outings due to their large water requirements.

Recirculating Equipment or Recircs

These are variations on other equipment but instead of relying on an external water source, they use a recirculating water system. Water is better at separating out gold than dry methods but also requires more equipment and time to set up. Rockers, high bankers, trommels and any other equipment that use water for separation can be altered to recirculate the water. These are very common in desert areas where water is scarce. Several club members have these and many are either handmade or altered after purchase. See specific types of equipment for examples.

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References

On Line References

Other References

  • Placer Examination, Principles and Practice, Technical Bulletin 4, U.S. Department of the Interior, Bureau of Land Management has lots of interesting information as well as plans for a rocker. This has been reprinted many times and is usually easy to find.
  • A good description of dry panning can be found in an inexpensive paperback, GOLD PANNING IS EASY by Roy Lagal, Ram Publishing Company, 1978.

Notes on graphics:

  •  modified from miscA57.gif at Cool Archive Free Clip Art and Fonts
  •  modeled after swinger.gif, an animated icon at an unknown URL.
  • All other icons (or small graphics) created by Michael Jeffers and donated to the Tucson Desert Gold Diggers. Copyright © 2002 by the Desert Gold Diggers.
  • All large graphics and dividers created by Jamie Girard and donated to the Tucson Desert Gold Diggers. Copyright © 2002 by the Desert Gold Diggers.