Abstract: The sluice box mouth and sifter pan system includes a sluice box mouth and a plurality of stackable sifter pans. The sluice box mouth includes a substantially planar bottom plate with a first upright sidewall extending from a first edge of the plate and an opposing second upright sidewall extending from an opposing, second edge of the plate. One of the sifter pans can be removably positioned on the bottom plate. The first and second sidewalls each include an arcuate portion for engaging a peripheral wall of the pan and securing the pan to the sluice box mouth.

Abstract: A portable sluice box for efficient processing and classification of alluvial sand, gravel, detritus, or classification of rock that has been mined and crushed. Sluice having three stages of material classification including, a movable primary screen, viewable secondary screen, distributor box with flow control baffle, laminar flow stratification trough, and cleanable bottom riffle system.

Abstract: An apparatus includes a placer-gold processing system, including: (A) an upstream section; (B) a gold-concentrator assembly being configured to be in fluid communication with the upstream section; (C) a gold-detection assembly being configured to be in fluid communication with the gold-concentrator assembly; and (D) a magnetite-separator assembly being configured to be in fluid communication with the gold-concentrator assembly.

Abstract: Various embodiments of methods and systems are provided for mining alluvial gold deposits. The methods can comprise collecting feed from alluvium and washing the feed at high pressure. The feed can be separated into a plurality of separate fractions. At least one fraction is transferred to a metal sensor system using a conveyer, wherein when gold is detected in a piece of the fraction, an air blast can be targeted and delivered at the piece, with the air blast diverting the piece to a receiving container.

Abstract: The present invention relates to a method of extracting gold from placer gravel. Whereas conventional techniques are relatively effective in the processing of coarse gold particles, i.e. plus ten mesh tyler, the present invention finds application in recovery of gold particles of all sizes from submicroscopic through coarse nuggets larger than ten mesh tyler. A rotating sluice box uses centrifugal force to enhance the sluicing process, and a centrifugal amalgamator then extracts gold from the concentrate thus produced, under centrifugal force. Gold is removed from the mercury by conventional techniques.

Abstract: A movably mounted receptacle having perforations therein with hollow spigots connected to the receptacle in registry with the perforations and projecting substantially downwardly therefrom, these spigots being moved through a bed of the particulate material in a receiver while particles of the material move through the spigots. The spigots discharge the particles moving therethrough into the bed and agitate the bed during movement therethrough. A fluid medium is directed in the materials in the receptacle, this medium going through the spigots with the material particles and overflowing from the receiver, carrying lighter particles with it while heavier particles concentrate towards the bottom of the bed. The separating method involving the use of this apparatus.