Looking West from Yarnell Hill, AZ and a Rainbow for Les Bender
Name:
Gold Symbol: Au Atomic Number: 79 Atomic Mass: 196.96655 amu Melting Point: 1064.43 °C (1337.5801
K, 1947.9741 °F) Boiling Point: 2807.0 °C (3080.15 K, 5084.6 °F) Number of Protons/Electrons: 79 Number of Neutrons: 118 Classification: Transition Metal Crystal Structure: Cubic Density @ 293 K: 19.32
g/cm3 Color: Gold
Prospecting
for gold 101:
While you can find small amounts of natural gold
just about everywhere, finding concentrated gold deposits takes a little knowledge of just how gold gets around.
Gold is very heavy. Actually, gold is about 19 times as heavy as water - about 3 times as heavy
as iron. Knowing this makes finding it much easier. Because of its weight, gold will always sink to the lowest level as possible.
As rain, wind, freezing & thawing, and geologic disruptions move the earth around, gold is freed up and relocates to the
lowest point.
For example, take a rain storm on the side of a hill. As the
rain falls, little rivulets form, flowing down the hill forming larger and larger streams. As the water moves, it erodes the
earth and rock beneath it freeing the trapped gold. The gold, caught up in the fast moving water, will cascade down the hill
looking for the first crack, undercut, or obstruction along the way to sink into. Over the years, more and more freed-up gold
will collect in these cracks, making for some fine pickings if you are willing to look for them.
Same thing goes in a stream bed. Look for where the water slows during a flood. If the gold has a chance, it will
sink. Sample or test where the stream bends or widens, or where there are natural obstacles or falls. Even a rock or boulder
in a stream will disrupt the flow of water, causing the gold to fall to the bottom and collect. Don't be afraid to 'turn over
a few stones'!
*
Where to look for gold
Gravel bars usually found
on the inside of the river bends. Although the gold here is mostly small flakes to very fine, there sometimes is a lot of
it.
Where the stream levels out after a steeper part such as downstream of rapids or waterfalls.
Newly formed gravel bars.
Small streaks of gravel laying on
the bed rock but you will need some sort of sucker to retrieve it if it is underwater.
Down
stream sides of large boulders and other obstacles which because of size or other factors appear to have been there for a
long time.
Pot holes in the bed rock
Cracks in the bed rock.
In popular prospecting areas, the large, obvious cracks have most likely been cleaned out many times. Look for lines of moss
running along the bed rock. There is almost always a small crack under the moss and these cracks can contain a surprising
amount of gold.
Moss and grass roots near the river.
The high
benches. As a stream cuts deeper into a canyon, it can leave patches of gravel high on the canyon wall. These are called benches.
Look for round or rounded rocks well above the present high water level. Round or rounded rocks have lived in a river at some
time in their lives.
Always keep in mind that these are the most likely
places to find gold. There is an old saying: "Gold is where you find it." What this really means is, you
may find a spot that looks perfect and not find any gold at all or you may find a spot that looks like it would be barren
but you find a "bonanza." Just try to keep your mind open to all possibilities.
Fill the pan 3/4 full of gravel, then submerge it deep enough so it is just under
the surface of the water. Give the pan several vigorous shakes back and forth and from side to side, but not too vigorous
as to wash material out of the pan. The idea is to make a slurry out of all of the material in the pan. Once loosened from
the dirt/ore matrix the gold, having a specific gravity 19 times more dense than water, will easily settle to the bottom of
the pan.
*Important Tip* Be sure to break up any lumps of clay or root balls where fine
gold and gold dust often collects.
2. Change from the shaking motion to a gentle circular movement so the
material starts revolving in a circle. This process will cause most of the dirt and clay to dissolve and wash out of the pan.
Pick out the larger rocks after making sure that they are washed clean.
Repeat 1. and 2. of Step A to get the smaller
rock to the surface and to cause the heavier concentrates to settle.
Step B: Washing off lighter sand and gravel
1. Hold the pan just under the water and tilt it slightly away from you. Begin to swirl the water from side to side,
with a slight forward tossing motion. Take care, but with sufficient force to move the surface and the lighter gravel out
over the edge of the pan.
2. Leveling the pan and shaking it or stratifying the material in the pan from time to
time and shaking it back and forth will cause the light material to come to the surface and the gold and black sands to settle
to the bottom.
Repeat process 1. and 2. of Step B until there is only about one cup (or less) of heavier material
left in your pan. This material is usually called black sand or concentrate.
Step C: Washing off black sand and
concentrates
*Important Tip* At this stage I always use a second pan or tub to pan into
so I don't accidentaly loose any of the fine gold.
At this point, raise the pan completely out of the water,
leaving about an inch of water in the pan.
Tilt the pan slightly towards you and swirl the water slowly in a circular
motion to check the pan for nuggets and pieces that are easily picked out by hand.
Remember: try to only touch the gravel that you are removing so the oil from your hands doesn't float the
gold dust out of the pan.
Then submerge the pan again in water and repeat process 1. and 2. of Step B for final
concentration. This is the most critical part of panning. Make sure this final process is accomplished with as much diligence
as possible so you do not wash out the gold.
If you have a plastic pan, the use of a magnet can quickly aid in
the separation of gold from the black magnetic sand concentrate. Apply the magnet to the bottom side of the pan and move it
in a small circular motion with the pan slightly tilted. This will work well to isolate the gold from the black sand.
Pick the gold flakes out with your tweezers and put them in your small glass vial.
*Important
Tip* To speed up the final steps, squeeze a couple of drops of the dish soap into the pan. This breaks the surface tension
and keeps the gold from being easily washed out of the pan.
In the United States the purity
of gold is designated by karat. Pure gold is 24k, but, because of its softness, it is not suitable for making jewelry. Other
metals such as copper, silver, nickel, and zinc are added to gold to strengthen it. What is added and how much is added determine
the color and karat of the gold. To make this easier to understand let's take an imaginary ring and examine it. The color
of the metal is immediately apparent. Gold comes in several colors, but let's pretend that this ring is pink gold. Inside
the ring is stamped 10k. What do these things tell us? First, that the gold was mixed with copper, silver and zinc to make
yellow gold. The pink look was achieved by using a larger quantity of copper. The 10k mark assures that 41.67% of the metal
is pure gold, and the other 58.33% is copper, silver and zinc. It also indicates that the piece was made in the United States.
(other countries do not use 10k). A 14k stamping would mean that the ring contained 58.33% gold and 41.67% other metals. If
the ring was marked 18k, it would contain 75% pure gold and 25% other metals. In Europe gold is stamped according to its fineness.
Pure gold is 1000 fine; 18k gold is 75% or 750 fine. Consequently, an 18k ring made in Europe would be stamped 750. Below
is a chart of the most common karat markings.
