Recirculating Mini Highbankers Metal Detectors
Gold Prospecting Equipment
Getting interested in gold prospecting means getting interested in gold
prospecting equipment. Those of us that have been at this hobby for a number of
years realize that gold prospecting equipment falls into two categories: The equipment we have and the equipment we
want to have. By the time they've been prospecting for a couple of years most
prospectors will have accumulated a number of pieces of equipment. Gold pans, dredges, sluice boxes
and highbankers for when wet recovery methods are to be used. Drywashers,
rockers, dry vacs and even gold pans can be used for dry recovery methods when there is no water available
for placering. Crevicing tools like pry bars, brushes, hammers, scoops and the
like are used for both wet and dry recovery. Once you get the black sand concentrates that come from the use of
these tools, clean up equipment is used. Some prospectors are good at using a
gold pan for such cleanup but there are also other tools available like mini-sluices, spiral panners, blue
bowls and such. Most of these tools are variations on technology that has been
available for hundreds of years.Some modern design methods have improved the basic function of these tools and
the use of electric or gas powered motors have increased the production
efficiency to a great degree. One technology for gold recovery that is completly modern is the vlf or PI metal
detector. Most prospectors get into metal detectors as a gold recovery tool at
one stage or another. For some prospectors, it's the preferred method and nugget hunting or nugget shooting has
grown into a specialized hobby all it's own with it's own specialized equipment.
Dry Recovery Equipment
What happens when the water dries up, how do you get the gold? A lot of gold
bearing areas are devoid of water or the water is seasonal at best. Places like
Arizona or the deserts of southern California are often dry places that see
little or no water for months at a time. For situations like this, dry recovery
methods are necessary and that is what the drywasher was made for. Drywashers
are similar to sluice boxes but they don't require water to operate. Unlike a
sluice box, the riffle box on a dry washer uses air to stratify the gold bearing
material. In a drywasher, the riffles sit on top of a breathable material like
canvas and a bellows pushes air up through to the riffles where the lighter
material is winnowed off into a pile while the heavier black sands and gold are
left behind in the box. Dry washers are made in a number of sizes from
small backpack drywashers which use a hand crank bellows to larger two or three
man drywashers which run the bellows on a gas powered motor. Choosing a gas
powered drywasher or a hand crank bellows model depends largely on where you
will be prospecting and how much material you want to move and how many people
will run the equipment.
Some people prefer wet recovery over dry recovery no matter what. It's generally
believed that wet recovery of gold is more efficient than dry recovery and so
they carry water and use recirculating sluice boxes.
In dry recovery, the gold panof course has it's place. A gold pan itself can be used
for dry recovery. Although not a method often used, dry panning can be used to
recover gold in desert areas. Dry material is placed in the gold pan, winnowed
and sloughed off to leave black sands. Recovery of gold from dry panning is
often finished later when concentrates can be packed back to water or when a
small amount of water is available. Pinpointers or small metal detectors can
also be used to recover flakes of placer gold from the end result of a dry
panning session.
Final
Clean Up Equipment
While many prospectors find that the gold pan is the simplest tool for final
cleanup on a placering project, there are quite a few pieces of specialized
equipment made just for this purpose. Many people choose to use a spiral panner
for their final cleanup and some even use it in preference to a gold pan for
production although it's not as efficient as a gold pan for that purpose. After
a panning, sluicing or dredging session, the final concentrates are scoop fed
into the spiral pan which is a round device with spirals leading up to a final
recovery cup. A spray bar and pump suck and recirculate water from a tub. The
spray of water washes the black sand concentrates. The lighter black sand is
washed back down to the bottom of the spiral pan while the heavier gold which is
less affected by the spraying action of the water rests on the riffles and is
moved upward in a series of spiral motions to be deposited clean in the cup.
Some prospectors prefer a device called a Blue Bowl. The Blue Bowl is a bowl
with a cone in the middle that rises up to a hole with a cup. Water is
recirculated in the bowl and small amounts of black sand are fed into the bowl
which spins, powered by an electric motor which can be operated by battery or
wall socket. In an opposite action to the spiral panner, the Blue Bowl, through
it's spinning action causes the black sand to rise up the center cone because of
centrifugal force to be deposited in the center cup, thus leaving the fine gold
behind in the bowl free of black sand where it can be collected by a snuffer
bottle.
For larger clean up jobs, shaker tables are used. These machines can clean large
amounts of gold bearing concentrates at a time. These shaker tables sit at an
angle and are motor driven to shake the concentrates along a series of riffles
in the table. Shaker tables are the preferred devices for final recovery on
large placer operations or to concentrate crushed ore from a lode mining
venture.
Metal Detectors
The advent of the modern metal detector could be seen as the single most revolutionary advance in gold prospecting. Thousands and thousands of gold nuggets have been recovered since the first BFO type detectors were invented for gold prospecting. Other mini revolutions have occured with each advance in metal detector technology. Both the VLF (very low frequency) and PI (pulse induction) gold detectors are still used today and technology continues to improve. Some prospectors have moved on from most other recovery techniques and rely on the metal detector alone to find placer gold. They main advantage of the gold detector is that it cuts out the middle man so to speak. A skilled gold detectorist can quickly find ounces of placer gold without having to run tons and tons of material through more traditional pieces of gold prospecting equipment, assuming they are in the right place to do so.
Not just any detector will work for finding gold nuggets however. One must have a detector that is suited for the task and that can be found in a modern VLF or Pulse inductiion machine. In order to succeed as a nugget hunter, one must have a good working knowledge of prospecting AND the right machine for the job as well as a working knowledge of how to use a gold detector properly. Without all three factors in place, the new user might find the metal detector to be a frustrating piece of equipment at best.
Still, many gold nuggets are found each year with metal detectors by beginners and seasoned prospectors alike.
Used Gold Prospecting Equipment
Regardless of the method of recovery you prefer, if you have a budget, it's always good to look into used gold mining equipment. Obviously, there are certain advantages to new equipment such as warranties and dealer support and sometimes this is preferred, however, it might be wise to look into used equipment because the savings can be substantial and for something like a sluice box or a dry washer a warranty might not be at the top of the priority list. Obviously, if you need a particular piece of prospecting equipment and cannot afford to buy new, go for used prospecting equipment. Good places to look include, your local mining shop, classified ads or Craigs list if you live in a mining area and of course, eBay.
