33
TEKNETICS
Comprehensive Operating Manual & Guide to Metal Detecting
Detecting Activities (continued)
Gold is valuable because it is a scarce commodity. Even in a good gold producing area, you
may spend an entire day without finding any gold. Meanwhile you may dig bits and pieces of
other metal. “Hot rocks” -- rocks containing concentrations of iron oxides that sound like metal
when you pass over them -- are also a nuisance in many gold areas.
If you have gone many hours without finding gold and are wondering if there is something wrong
with your metal detector or how you are using it, the most important clue is this: if you are digging
tiny pieces of trash metal, then if you had swept over gold nuggets, you would have dug them too!
When something that sounds like gold has been detected, most of the time it’s iron metal or a
hot rock. Always carry a strong magnet, and stick the magnet into the dirt where the detected
object is. Iron will be drawn to the magnet, and hot rocks usually will be as well. Even if you
pull iron metal or hot rocks out, always check again with the metal detector to see if there is
gold (which of course won’t be drawn to the magnet). A good magnet is what a gold
prospector uses instead of “discrimination mode”.
Most gold nuggets are very small, and are most often found in soil which is high in iron oxide
minerals. Therefore serious gold prospecting requires a detector with high sensitivity and with
true ground balanced motion all metals operation. Run the machine with the sensitivity high
enough to hear some noise from ground minerals, and learn the language of the sounds you
hear. Most prospectors prefer to use headphones unless consideration for safety (for instance
rattlesnakes) rules them out. Move the searchcoil slowly and deliberately, carefully controlling
its height above the ground to minimize noise from iron minerals in the soil. If you hear ground
noise, your ground balance setting could be a bit off, so perform the ground balancing
procedure again. In some areas the ground changes over very short distances and you’ll
have to pay close attention to ground balance.
Some “gold machines” display the amount of iron mineralization in the ground. In alluvial
(placer) deposits, gold tends to be associated with iron minerals, particularly magnetite black
sand. If you know this to be the case in the area you're working, you can maximize your gold
recovery by concentrating your effort on areas where the display indicates higher amounts of
iron mineralization.
Remember to always carry a magnet when gold prospecting. And follow these guidelines:
Using a magnet as a “hot rock discriminator”- a summary
• Iron metal is always strongly attracted to a magnet. Steel (iron alloys) are almost always
strongly attracted to a magnet.
• Magnetite hot rocks and black sand are always strongly attracted to a magnet.
• Other negative hot rocks are almost always attracted to a magnet, but not as strongly as
magnetite.
• Positive hot rocks are usually attracted to a magnet, but the attraction is often weak.
• Meteorites detected by a metal detector are usually attracted to a magnet. The
attraction may be strong or weak.
• Gold and other nonferrous metals are never attracted to a magnet.
