Abstract: Material collection devices, placer recovery systems, and related methods are disclosed. A material collection device includes a filter tube including a wall defining apertures, an inlet through which fluid and material enter the filter tube, protrusions extending inwardly from the wall of the filter tube, the protrusions in front of the apertures from a perspective of the inlet, and an outlet through which the fluid and material exit the filter tube. The material collection device also includes a collector positioned below the filter tube, the collector configured to collect particles of the material that exit the filter tube through the apertures.

Abstract: A slurry handling apparatus includes at least one reception hopper includes a base, a rear wall and opposing side walls, and an opening provided in the base. Slurry delivered into the reception hopper from a tanker can pass through the opening in the base, and a respective first dewatering screen having an apertured screening deck is located beneath the at least one reception hopper so that slurry passing through the opening is delivered onto the deck of the respective screen, with undersize material and water passing through the apertures of the deck to be received within a sump, and with oversize material passing over the deck to be discharged from a downstream end of the deck.

Abstract: A classifier device for separating heavy materials from a stream of water and lighter materials includes an upper deck above lower deck, each deck having entrance and exit sides. The exit side of the lower deck terminates in a plurality of apertures. An exit plate is disposed adjacent the exit side of the upper deck and elevated relative thereto. A trap compartment is disposed below the exit plate and receives a removable trap that has an open top side and a plurality of pipes that each have at least one fluidizing aperture and that are aligned with one of the apertures of the lower deck. A classification plate is included between the exit side of the upper deck and the exit plate for directing the larger light materials up and over the exit plate back into the stream of water. Smaller materials drop through the classification plate into the trap.

Abstract: A sluice box is described comprising two walls, and a plurality of riffles. Riffles can have a first portion that extends below the bottom panel of a sluice box (or the bottom of a flow), and a second portion that extends above the bottom panel of a sluice box (or the bottom of a flow). By creating a catch in a riffle by having a portion of the riffle extend below a bottom panel of a sluice box, heavier minerals are not washed away as quickly, if at all, as with other sluices.

Abstract: Portable flexible sluice box with airfoil-shaped flare is a flexible sluice box. The entire portable flexible sluice box with airfoil-shaped flare can be rolled up into a compact cylindrical roll. Portable flexible sluice box with airfoil-shaped flare comprises a flexible airfoil-shaped flare attached to a flexible riffle sheet. Flexible airfoil-shaped flare is a tube of flexible material partially filled with particulate matter to yield a flexible tube member with an airfoil-shaped cross section when laid out laid out flat on a horizontal surface. Flexible riffle sheet is a rectangular-shaped flexible sheet of material with a plurality of parallel ridges protruding from its upper surface. Portable flexible sluice box with airfoil-shaped flare may further comprise a set of two wall insert pockets and a set of two rigid inserts. This optional structure essentially adds a wall to the left and right edges of flexible riffle sheet.

Abstract: The invention relates to a method and system for monitoring of particles properties in a stream and the use of such method and system. In particular, the invention concerns sampling of liquids like aqueous suspensions or filtrates that contain solid matter in forest industry, oil and mining industry, as well as in and water treatment, desalination or water reuse processes, and in subsequent measurement of the samples. A sample from a stream of liquid is dyed to stain particles contained in the sample, which is conducted to a first flow chamber having means for causing said sample to be divided into particle populations according to their size or mass. A liquid flow is applied through the first flow chamber to cause at least one particle population to flow into a second flow chamber.

Abstract: A sluice box separator apparatus having a curved partition wall to shape the water flow into a horizontal vortex, inducing lighter material to exit the vortex with the water, and the denser materials to settle into a well located beneath the location of the induced vortex, including a selectively openable gate between the well and a valuable material recovery chamber.

Abstract: An ultrasonic microfluidic system includes a separation channel for conveying a sample fluid containing small particles and large particles, flowing substantially parallel, adjacent to a recovery fluid, with which it is in contact. An acoustic transducer produces an ultrasound standing wave, that generates a pressure field having at least one node of minimum, pressure amplitude. An acoustic extension structure is located proximate to said separation channel for positioning said acoustic node off center in said acoustic area and concentrating the large particles in said recovery fluid stream.

Abstract: An ultrasonic microfluidic system includes a separation channel for conveying a sample fluid containing small particles and large particles, flowing substantially parallel, adjacent to a recovery fluid, with which it is in contact. An acoustic transducer produces an ultrasound standing wave, that generates a pressure field having at least one node of minimum pressure amplitude. An acoustic extension structure is located proximate to said separation channel for positioning said acoustic node off center in said acoustic area and concentrating the large particles in said recovery fluid stream.

Abstract: A mineral separating gold cube concentrator presents at least two modular portable stacking trays defining alternating inclined surfaces over which a continuing supply of water flows. A first tray provides an inclined smooth surface with controlled water flow to the incline which imparts fluidity allowing the aggregate to move downward and form a slurry that separates the aggregates into lightest first, heaviest last. A second tray is a collection tray is below the first tray and defines a G force separator, forcing all materials under the gate into vertical column within the turbulent water, the column descending upon the vortex mat upon the second tray, forcing the lighter materials within the aggregate to advance ahead of the heavier material. Any material not captured by the vortex mat travels to the end of the matting and is either expelled or subsequently transferred into another collection tray through another G force separator.

Abstract: A portable device for use in the efficient extraction of gold from other materials commonly found in placer deposits of gravel, sand and etc. This is accomplished by utilizing two sub-assemblies easily attached to existing gold recovery equipment such as the common gold sluice and etc. This is accomplished by utilizing four sub-assemblies. Two on opposite sides and also two on opposite ends of the sluice tray. Each sub-assembly consists of a side bracket 14 and leg socket 18, which are conjoined by means of leg socket retaining fasteners 32. These are in turn are attached to cross brace 20 by means of side bracket positioning screws 28. Two sub-assemblies are attached to each other on opposite sides of the sluice tray and conjoined by means of shoulder bolt 22, washer 24 and retaining nut 26. After secure attachment of the two opposite sub-assemblies the legs are inserted into leg socket 18 and held in place by locking screw 16. These same actions are then performed on the opposite end of the gold sluice.

Abstract: A portable device for use in the efficient extraction of gold from other materials commonly found in placer deposits of gravel, sand and etc. This is accomplished by utilizing two sub-assemblies easily attached to existing gold recovery equipment such as the common gold sluice and etc. This is accomplished by utilizing four sub-assemblies. Two on opposite sides and also two on opposite ends of the sluice tray. Each sub-assembly consists of a side bracket 14 and leg socket 18, which are conjoined by means of leg socket retaining fasteners 32. These are in turn are attached to cross brace 20 by means of side bracket positioning screws 28. Two sub-assemblies are attached to each other on opposite sides of the sluice tray and conjoined by means of shoulder bolt 22, washer 24 and retaining nut 26. After secure attachment of the two opposite sub-assemblies the legs are inserted into leg socket 18 and held in place by locking screw 16. These same actions are then performed on the opposite end of the gold sluice.

Abstract: Various traveling wave grid configurations are disclosed. The grids and systems are well suited for transporting, separating, and classifying small particles dispersed in liquid or gaseous media. Also disclosed are various separation strategies and purification cells utilizing such traveling wave arrays and strategies.

Abstract: A reflux classifier for segregating particles by size or density using a fluidized bed in a chamber. Arrays of inclined plates form lamellae and divide the chamber into zones into which particles of predetermined size or density migrate. Particle differentiation is controlled by plate length, inclination and spacing in each array, combined with fluidization rate.

Abstract: The log washer with staggered paddles is a device for washing and separating aggregates, such as sand, gravel, ores, etc., from waste material. The log washer has a water tank or trough having one end inclined or raised relative to horizontal. A pair of shafts are mounted for rotation in bearings in the end walls of the tank, and connected to a driver by appropriate gearing so that the shafts rotate in opposite directions. Each shaft has a plurality of paddles mounted thereon, each paddle being mounted at an angle to the shaft to raise washed aggregates up the inclined trough to a discharge hopper or conveyor belt. Further, the paddles on each shaft are grouped in sections, the radial angle formed by adjacent sections with the shaft being staggered, the paddles on adjacent shafts being offset so that the aggregate material is ground between the paddles.

Abstract: A device for reclaiming material, such as used wet ready mixed concrete, having a hopper for receiving the used concrete into a excess of water and floating the suspended cement particles out through a weired overflow for further reclamation while the solid sand and aggregate is augured from the bottom of the hopper for further washing and separation into sand and aggregate for reuse.

Abstract: Replaceable inserts are provided in depressions of a spiral separator wherein the inserts have surface irregularities to optimize the spiral efficiencies in separating feed stock materials. These irregularities become worn by the materials and would require replacement of the spiral, ordinarily, whereas new inserts herein greatly extend the useful life of the spiral. Also, if the feed of the spiral changes appropriate new inserts may be used to separate the changed feed. The inserts may be any shape, circular being preferred when adjustability is needed.

Abstract: A placer gold separating method includes subjecting placer gold-and gold ore-containing sand and gravel layers accumulated on the bottom of the water of a river and placer gold- and gold ore-containing sand and gravel layers formed deep in the ground to excavation or suction excavation by utilizing a water pressure difference. This causes a mixture of the excavated or suction excavation placer gold- and gold ore-containing sand, gravel and water to flow horizontally by the action of a pressure fluid. The placer gold and gold ores are separated by utilizing a specific gravity difference while the mixture is flowing. A placer gold mining boat used to practice this method is provided thereon with a combination of a suction excavation component, a mixture transfer component, a component for separating placer gold by utilizing a specific gravity difference, and a component for discarding the remaining mixture from which the placer gold has been separated.

Abstract: A mining system and related methods are disclosed by which gold and/or other heavy metals are recovered at multiple sites along a continuously hydrated ore processing route. The gold-bearing ore and primary or carrier water are dynamically and circuitously displaced to segregate the gold, and precipitate the gold particles into predetermined recovery sites along the flow path of the mix. Boil box recovery sites are selectively provided for recovery of nuggets and smaller particles. Secondary water churns and disrupts the primary carrier flow of the mix through each boil box. Availability and reuse of massive amounts of carrier and secondary water are important.

Abstract: A small sluice for final separation of gold from all other materials commonly found in deposits of gravel, sand, etc. including a bottom panel (14) with a plurality of grooves (16), two substantially vertical sidewalls (15), a flared entrance end (13) and device for closing (18) the flared entrance end (13). This sluice is suitable for many uses including the cleanup of concentrates from panning and sluicing operations and for prospecting sampling.

Abstract: A mining system and related methods for recovering gold and/or other heavy metals at multiple sites along a continuously hydrated ore processing route. The gold-bearing ore and primary or carrier water are dynamically and circuitously displaced to segregate the gold, and precipitate the gold particles into predetermined recovery sites along the flow path of the mix. Boil box recovery sites are selectively provided for recovery of nuggets and smaller gold particles. Secondary water churns and disrupts the primary carrier flow of the mix through each boil box. The master stream of gold-sized ore-primary water mix is subdivided into several separate streams or substreams. The sub streams are violent in nature, with one exception, and are typically contained in man-made canal-forming troughs or multiple recovery sits. Recovery sites have one or more drop slots. A downward draw caused by flow of secondary water in a conduit located below each slot enhances recovery.

Abstract: A mining system and method for recovering gold and/or other heavy metals at multiple sites along a continuously hydrated ore processing route. The gold-bearing ore and primary or carrier water are dynamically and circuitously displaced to segregate the gold, and precipitate the gold particles into predetermined recovery sites along the flow path of the mix. The master stream of gold-sized ore-primary water mix is subdivided into several separate streams or substreams. The substreams are violent in nature, with one exception, and are typically contained in man-made canal-forming troughs having multiple recovery sites. Recovery sites comprise one or more drop slots. A downward draw caused by flow of secondary water in a conduit located below each slot enhances recovery. Each trough includes a dynamic segregation box having successive compartments across which a top layer of turbulent flow continuously occurs.

Abstract: A mining system and related methods for recovering gold and/or other heavy metals at multiple sites along a continuously hydrated ore processing route. The gold-bearing ore and primary or carrier water are dynamically and circuitously displaced to segregate the gold, and precipitate the gold particles into predetermined recovery sites along the flow path of the mix. Boil box recovery sites are selectively provided for recovery of nuggets and smaller gold particles. Secondary water churns and disrupts the primary carrier flow of the mix through each boil box. The master stream of gold-sized ore-primary water mix is subdivided into several separate streams or substreams. The sub streams are violent in nature, with one exception, and are typically contained in man-made canal-forming troughs or multiple recovery sites. Recovery sites have one or more drop slots. A downward draw caused by flow of secondary water in a conduit located below each slot enhances recovery.

Abstract: A sluicing operation for entertainment comprises a two portion unit, having storage facilities and sluicing area with at least one trough at approximately a 2.degree. angle. The storage facilities have a water/ore separation unit, precious material holding bin with measuring device, conveyor and ore weighing device. The conveyor transports the precious material and ore to a holding unit where it is dispensed. Pipes circulate the water or ore/water combination. The bottom of the trough can be mesh, the ore filtering through onto a second conveyor where it is carried to an ore receiving area. A flared side sluicing pan with a perforated base separates the highly polished ore and precious material. A controlled artificial river forms a permanent sluicing operation using passive filtration dams with controlled inlet ports. The water is filtered through filtration matting before entering the inlet ports. The riverbed is filled with gemstone and gold enriched sand and gravel.

Abstract: A continuous cycle apparatus for separating particles of precious metals from concentrate having a funnel-shaped hopper. A pump circulates a portion of the water from a sump into the hopper to create a vortex of water and concentrate such that less dense material tends to overflow from the hopper into the sump. The pump also circulates a portion of the water from the sump through a tube connected to a bottom opening in the hopper to transport concentrate and water to a sluice box which collects particles of precious metals contained in the slurry. The rate at which water and concentrate are drawn from the hopper is adjustably controlled by a metering rod located in the tube immediately below the bottom opening in the hopper. The water and remaining particles drain from the sluice box back into the hopper to complete the cycle.

Abstract: A machine is employed for recovering heavy metals, such as gold, from placer ore. The machine employs a cylindrical, annular outer drum mounted for rotation at an inclination to the horizontal and including at least one spiral vane extending the length of its inner surface. A cylindrical, annular inner barrel is mounted within the drum and has an upper fragmentation section, an intermediate trommel section, and a lower discharge section. A spray of water is directed into the inner barrel and a water spray bar is located in the annulus between the inner barrel and the outer drum. A sluice box is located to receive an input discharge from the upper end of the outer drum. The ore is separated into large tailings that are discharged from the lower end of the inner barrel and fine, light tailings from the outer drum.

Abstract: A hydraulically operated set of riffles includes a network of spaced-apart tubular riffle bars arranged to lie above a collecting surface in a riffle box. A plurality of generally downwardly directed apertures is formed in each riffle bar, and a flange extends generally upwardly along the length of the riffle bar. An inlet of each riffle bar is connected to a source of water or other fluid. In operation, water or other fluid that is supplied to the riffle bars passes forcibly outwardly through the apertures and is subsequently constrained to flow outwardly through the spaces between adjacent riffle bars to prevent undesired accumulation of particles between adjacent riffle bars.

Abstract: Apparatus (10) for hydraulically separating a mixture of small size mineral particles (42) according to different mineral densities (61 and 91) consists of an elongated inclined tubular conduit (11) which includes appurtenances and adjustments by which the innately higher midstream velocity and lower, conduit sidewall surface velocity forces of the adjusted upward fluid flow through the inclined conduit (11) are systematized for the processing. In combined operations the mixed feed particles (42), after introduction at intermediate longitudinal location (31) of the inclined conduit (11), drop rapidly out of fluid flow suspension and are processed while continuously maintained in a predominantly precipitated condition. During processing, the precipitated particles (42) are formed into a more or less continuous layer of two superincumbent strata which move or tend to move relatively in opposite longitudinal directions throughout the length of the inclined conduit (11).

Abstract: Portable sluice equipment is provided for miners backpacking into back country to separate out valuable metals from placer deposits. All major components are made from commercially available PVC plastic conduits and fittings. The principal component is a sluice trough manufactured by first longitudinally cutting a plastic pipe in half, and then cutting spaced transverse back angled radial flow channel grooves throughout the sluice trough to initially receive the concentration of heavy metals. Also longitudinal grooves are cut throughout the length of the sluice trough near the respective top edges. Then when periodically, the main flow of sluicing water is stopped, the sluice trough is rotated about its longitudinal axis, and a minimal flow of water is directed transversely to flush the heavy metals from the transverse back angled radial flow channel grooves into the longitudinal groove.

Abstract: A process of using an apparatus (10) hydraulically separating a mixture of small size mineral particles (42) according to different mineral densities (61 and 91) consists of an elongated inclined tubular conduit (11) which includes appurtenances and adjustments by which the innately higher midstream velocity and lower, conduit sidwall surface velocity forces of the adjusted upward fluid flow through the inclined conduit (11) are systematized for the processing. In combined operations the mixed feed particles (42), after introduction at intermediate longitudinal location (31) of the inclined conduit (11), drop rapidly out of fluid flow suspension and are processed while continuously maintained in a predominantly precipitated condition. During processing, the precipitated particles (42) are formed into a more or less continuous layer of two superincumbent strata which move or tend to move relatively in opposite longitudinal directions throughout the length of the inclined conduit (11).

Abstract: A portable sluice box for classification of mineral particulate from detritus or placer deposits containing the same is comprised of an infeed table including upstanding sidewalls and a bottom wall for receiving and confining a charge of mineral-containing deposits for fluid compelled movement along a path lying in a material handling plane generally coincident with the bottom wall of the table; a classification table member, including upstanding sidewalls and a foraminous separation plate having downwardly depending, opposed marginal skirts for proximal engagement with the sidewalls of the separation table interiorly thereof, the separation plate also lying within the material handling plane; a plurality of riffles disposed transversely in a laterally and longitudinally extending spaced array between the skirts, defining a series of upper flow channels intermediate the separation plate and the top edge of the riffles and a lower, mat channel intermediate the bottom wall of the classification table and the bo

Abstract: Heavy minerals such as gold, silver, platinum, etc., along with gemstones such as diamonds, rubys, sapphires, etc., occuring in nature in the free state or having been mechanically released by crushing, screening and/or sorting into a free state, can be separated from the common material, into which they are mixed, by applying water to the mixture of materials and allow their different specific gravities to separate them into the bottom of a grooved trough. In the novel mineral concentrator described, to minimize the loss of water, a recirculating pump re-uses the same water from a reservoir repeatedly. The free minerals and gemstones settle out of the main water flow and are trapped into grooves and other pockets and crevices. Some of the pump's water flow is allowed into a feed hopper to wash down the hopper's walls, and in conjunction with shaped apertures in the hopper bottom, automatically regulate the flow of material entering the main trough or sluice.

Abstract: This invention relates to an apparatus for separating materials of small size. The apparatus according to the invention comprises a separation tub which can be filled with a liquid up to a preselected level, means for introducing a conveying liquid with the materials to be separated into the tub below said preselected level under a pressure which is higher than that existing the area of introduction due to the effect of the weight of the liquid in the tub, and first and second material-ejection means arranged at said preselected level and, respectively, at the tub bottom to eject lighter and, respectively, heavier material.

Abstract: A placer mining sluice for separating relatively heavy particulate valuable materials from relatively light waste material. The mining sluice includes an inverted generally V-shaped grizzly screen having first and second sides which slope downwardly and outwardly from a longitudinal axis of the screen. First and second panels are positioned at opposed ends of the screen to close off the ends of the screen. A deflector pan having opposed first and second ends is positioned beneath the grizzly screen to extend between the first and second screen sides and between the first and second screen ends. The first end of the pan contacts the first panel. A tray is positioned beneath the deflector pan and screen at an angle relative to the horizontal with the uppermost tray end beneath the second end of the deflector pan. Material passing through the screen passes over the deflector pan second end onto the uppermost end of the tray.

Abstract: A sluice box apparatus for recovering heavy material, such as gold, comprises a fine recovery channel and a coarse recovery channel. The recovery channels have receiving ends, riffles and matting for collecting fines of the material. A hopper at the receiving end of the channels has a receiving end for aggregate, a discharge end adjacent the receiving ends of the channels, a bottom, an open top and water distributing means near the top and the discharge end for washing fines from the aggregate. A perforated plate extends substantially across the hopper near the discharge end. The plate is spaced-apart from the bottom. There is a coarse material discharge opening adjacent the coarse recovery channel for a flow of water and aggregate passing over the perforated plate to the coarse recovery channel and a fine material discharge opening between the bottom end and the perforated plate and adjacent the fine recovery channel.

Abstract: This invention pertains to a method and apparatus for removing compacted, slurriable solids from a vessel by water erosion. The water erosion is effected by a waterfall created through the use of a travelling bridge which traverses the compacted solids and coacts with a movable gate which allows a nearly vertical face of the compacted solids to be exposed to the waterfall.

Abstract: A device for separating and recovering solid particles or granulated matel from a stream of fluid in a state of high purity and with minimal fluid remaining in the recovered solids. The device also provides a calibration or sizing of the recovered solids. More particularly, the device is suitable for recovering sand and gravel from a liquid slurry in dredging operations or the like and comprises a chamber into which the slurry is discharged in the form of two diametrically disposed impinging jets to decrease the kinetic energy of the slurry. The chamber is provided with one or a plurality of outlets disposed in communication with a corresponding number of channels each having a discharge port in the base thereof and a deflector in the discharge port, preferably disposed at an angle of about 45 degrees, for directing the concentrated lower layer of slurry in each channel through the discharge port into a deposition tank.

Abstract: A gold concentrator comprises a housing at the end of a sluice into which a quantity of sand, rock and gold particles is deposited. A screen on a portion of the sluice serves to segregate larger particles of rock and gold from the finer sand particles. A hose is attached to the rear wall of the housing and water under pressure mixes with the finer sand. The mixture of sand and water strikes a wall and a depending flange within the housing causing the mixture to turn over therein thus creating a suspension of particles within the liquid. The suspension falls onto the sluice and flows downwardly therealong and over the screen at the bottom thereof. A flange at the end of the sluice turns the suspension in the opposite direction where it flows down a forwardly extending second sluice. The forwardly extending second sluice has a rubber mat thereon having a series of transversely extending grooves which function to trap the gold and black sand particles therein.

Abstract: An improved continuous run sluice box having a sonic vibration and ultrasonic vibration means for concentrating gold or other precious metals while eliminating the loss of black sands containing other valuable fines normally accompanying the use of conventional sluices. The sluice includes a novel type riffle construction including a vertical wall and a sloping wall leading to a collecting area having a nylon cloth screen positioned between coarse and fine metallic screens which facilitates both the collection of the fines and the release of the same during flushing operations.

Abstract: A pan for separating gold or other precious heavy metals from wet sand or gravel is provided with a round bottom joined to obliquely rising sides at the circumference. Near the center of the bottom of the pan is an aperture leading to a trough which is formed integrally with the bottom and slopes downwardly therefrom. Within the trough is a ladder-like structure having a plurality of steps which collect the heavy metal particles from the dross.

Abstract: Apparatus for continuous flow classification and specific gravity separation of relatively fine, heavy sands from gravel and dirt aggregate comprises an elongated channel having an apertured top plate which defines an upwardly facing flume and a cavity. The flume is adapted to have a flow of water bearing the aggregate introduced at its upstream end to flow over the top plate so that the relatively smaller, heavier material falls through the apertures into the cavity. An inclined table is positioned in the cavity below the top plate, the angle of inclination of the table being adjustable. The table has a trough defining side portions and terminating in a downstream extension for discharging tailings, the extension having an opening communicating with the sump portion of the cavity. An adjustable weir diverts flow of a selected heavier portion of the material from the trough into the cavity sump.

Abstract: A sluice box is disclosed for use in high volume placer mining operations and a method of placer mining is disclosed, which are particularly useful for the recovery of gold from aggregate material. In operation, aggregate material is loaded into an inlet trough of the sluice box where it is mixed with water to form a slurry. A coarse recovery channel leads from the inlet trough and the sluice box is downwardly inclined, so that the slurry flows through the sluice box. The inlet trough has a punch plate bottom for separating the slurry into a coarse slurry stream which passes on into the coarse recovery channel, and a fine slurry stream which drops through the punch plate. A distribution section located below the punch plate has a generally conical and upwardly inclined floor, and angularly disposed vanes, so that the fine slurry stream is spread transversely and evened to produce a generally uniform cross-sectional flow profile.

Abstract: A splitter assembly is described of the type wherein a pulp stream is discharged from the discharge edge of a stratification surface across a gap to impinge against a splitter so as to separate into upper and lower flow components, the lower component passing through the gap while the upper component flows over the splitter, characterized in that the splitter has a generally curved impingement surface and is adjustable relative to the stratification surface such that the gap width in the direction of stream flow increases as the required lower flow component increases and decreases as the required lower flow component decreases. Preferably, the splitter is hingedly mounted for rotation relative to the stratification surface.

Abstract: A separating apparatus and method is provided by the use of which a stratified flow of a mixture of materials of different properties, for example, a slurry of mineral-bearing sand in water, can be separated into fractions by impinging a substantial proportion of the flow against a separator face assembly, for example, a separator plate.

Abstract: A gold sluice includes an elongated semicylindrical trough having angular corrugations therein for imparting a longitudinal turbulent flow to water moving gravitationally therethrough. The longitudinal spiral turbulence of the water promotes separation of heavy particles from a placer material placed at an upstream end of the trough. Gold, being a heavy metal, will settle into the corrugation grooves along the trough. The sluice further includes laterally projecting flanges on opposite longitudinal side edges of the trough for preventing the trough from overturning laterally. The sluice is formed of a single sheet of lightweight material with the semicylindrical trough extending integrally therein and with the corrugations formed integrally within the trough. The corrugations are angularly oriented with respect to the longitudinal axis of the semicylindrical trough configuration.

Abstract: Apparatus and method for separating heavy materials from ore, the apparatus having a hopper or sluice box open at its top and defining a discharge opening on one side. Spaced, parallel pipes extend across the hopper adjacent, but above, the bottom of the sluice box, the pipes having holes which direct the water sidewise toward the adjacent pipes. The holes of adjacent pipes are staggered with respect to each other. Shields or spreaders, disposed over the top portions of the pipes, protect the pipes from the ore which is charged into the open hopper, these spreaders directing the ore between the sprays of water to produce a slurry which passes out of the side discharge opening over a riffle or extractor, providing a downwardly inclined series of spaced parallel, transversely extending, upright barriers which snare and retain the heavy materials, such as gold and black sand. A plurality of these sluice boxes and ripples are juxtaposed on the flat bed of a truck. A common pump supplies water to the sluice boxes.

Abstract: Methods and apparatus for underwater mining by inducing upwelling of water and entrained minerals or other materials through a conduit from an intake which may move within the body of water by unbalanced forces developed therein by such upwelling to a recovery field which may comprise a vessel floating on the water and which may also be moved by the upwelling water. The outlet of the conduit to the recovery field is positioned below sea level and the velocity of the upwelled water in the recovery field is gradually reduced to induce selective separation of the entrained minerals or other materials.

Abstract: A dredge unit having a buoyant support carrying a sluice box suspended beneath, a water suction system connected to an outlet end on the box and a suction hose operatively connected to an inlet end thereof. The water suction system operates to draw water and material through the suction hose and into the sluice box where material of relatively high specific gravity is contained while the remainder and the water is discharged from the system.

Abstract: A portable sluice pan is described for panning for gold and other valuable heavy minerals from placer deposits. The pan includes an elongated trough having a feed hopper at one end and a removable flexible riffle mat in the bottom of the trough to cause the placer pulp to flow in a turbulent manner over the riffles to stratify the heavier and lighter materials. The sluice pan is constructed of light weight material such as aluminum and may be hand held during operation.