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ALLUVIAL EXPLORATION & MINING
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Small Mining
Dip-BoxThe dip-box is useful where water is scarce and where an ordinary sluice cannot be used because of the terrain. It is portable and will handle about the same quantity of material as the rocker. Construction is relatively simple. The box has a bottom of 1- by 12-inch lumber to which are nailed 1- by 6-inch sides and an end that serves as the back or head. At the other end is nailed a piece approximately 1 inch high. The bottom of the box is covered with burlap, canvas, or thin carpet to catch the gold, and over this, beginning 1 foot below the back end of the box, is laid a 1- by 3-foot strip of heavy wire screen of about 1/4-inch mesh. The fabric and screen are held in place by cleats along the sides of the box. Overall length may be 6 to 8 feet, although nearly all gold will probably collect in the first 3 feet. The box is placed so the back is about waist high; the other end is 1/2 to 1 foot lower. Material is simply dumped or shovelled into the upper end and washed by pouring water over it from a dipper, bucket, hose, or pipe until it passes through the box. The water should not be poured so hard that it washes the gold away. Larger stones (after being washed) are thrown out by hand, or a screen-box can be added to separate them. Riffles may be added to the lower section of the box if it is believed gold is being lost.
From: Bureau of Mines Information Circular 8517 by J.M. West, released in 1971.
Rafal Swiecki, geological engineer email contact January, 2007
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