Did someone pan this nugget from a stream using a gold pan? Nope - I picked this out of the back (roof) of a lead-zinc mine in Utah's Bingham district in the Oquirrh Mountains many years ago. It's not gold - its fools gold. If it were dumped in a creek it wouldn't take more than a few years (if that) to dissolve to rust (iron oxide) and sulfuric acid. BUT, if the pyrite crystals contained some hidden gold in their crystal lattice (which often happens with pyrite), so gold would also fall out in the water. Just how much gold can pyrite contain in its crystal lattice? Well, sometimes as much as an ounce of gold, and sometimes even a lot more which Eric and I described in our gold book. |
God Bless America!
For
those of us who are mechanically declined, gold pans
are great: no buttons, meters, scales, batteries, computer chips, or electronics. They provide a
break from today’s ubiquitous computers and electronics that frankly get on my
nerves. Ever go out to dinner just to see all of the people around you texting
on their phones and ignoring their company. Yes, I would just like to grab a
few of those people by the earlobes and take them out in the field to pan for
gold.
During
the 1849er gold rush in California,
more than 118 million ounces of gold was found by gold prospectors. Many of
these discoveries began with prospectors simply using tin dinner plates. When they
found gold in their pans, they starting looking up slope for lodes filled with gold. Those
who used diligent prospecting methods often found the source of the gold. In
those days, panning had two purposes: to search for gold and to clean a dinner plate.
Gold panners on one of my field trips along the Middle Fork of the Laramie River in Wyoming. No one found gold on this trip, but they learn to pan, got some good sunshine and air, and several recovered diamond indicator minerals in their pans. Diamond indicator minerals included minerals unique minerals that erode from diamond pipes. |
So
did the 49ers find all of the gold?
Nope, they only found the easy lodes. Remember, a lot of their gold came from placers
and placers eroded from nearby lodes. It is likely prospectors depleted
many of the better placers, but they barely scratched the surface of the
lodes! After searching for gold in Wyoming as a research geologist for 30 years, and a consultant for many companies, it is clear hundreds
of gold deposits were overlooked not only in Wyoming, but all over the world.
I found gold all over southern Wyoming not only adjacent to Interstate-80, but
even in the Laramie City landfill – all places no one had ever thought to look!
A book on how to identify and find gemstones has already led to new discoveries of opal, diamonds, rubies, sapphires, peridots and potentially diamondiferous host rocks by its readers |
Today,
the “Golden State”, home of the “Forty-niners”,
divorced its heritage and chose bankruptcy over mining. Not a bright thing to
do, but California’s politicians have never been accused of being smart. Not
only that, California no longer allows people to use hobby dredges to dig for
gold, even though the state was built on gold mining. Hobby dredges are
essentially harmless - and in some cases, they stir up food for fish.
One of more than a hundred field trips led by the author to
teach the public how to prospect for gold, diamonds and
other minerals.
|
And
where did those diamonds come from? No one has yet found the source of the
diamonds accidentally discovered by old gold miners. In the 19th
century (as today) few prospectors had knowledge of what diamonds looked like, particularly
since the great diamond rush in Kimberley South Africa, didn’t take place until
1871, twenty-two years after the great Californian gold rush. And it is likely thousands
of diamonds were mined with the Californian gold and were rejected with quartz
in the mine tailings, simply because the prospectors had no idea what the
diamonds were. The diamonds from California ranged from less than a carat to
one that weighed 32.99 carats (Hausel, 1998; Erlich and Hausel, 2002). It is
important to keep diamonds in mind while prospecting for gold, because some are
worth thousands of
times more than an equivalent weight of gold (after faceting), but then again, others are worthless. And many
collectors pay premium prices for raw natural diamonds from unique locations.
While panning for gold, one often sees curious bystanders. Photo by my beautiful daughter - Jessica. |
These
are not the only gemstones that have been found in California or elsewhere in
North America. A few years ago, while searching for diamonds in California, I recovered
several beautiful light-blue benitoite
gemstones from panned concentrates taken in the Sierra Nevada Mountains. Benitoite
looks very similar to sapphire. Further north in California, I also recovered pyrope garnet and chromian diopside.
In Wyoming, we
recovered gold from many areas where gold had not been reported. But we also
found gold right in the middle of areas where people had mined gold in
historical past. In addition to precious metals, we found gem-quality garnet, chromian diopside,
ruby and sapphire in streams, and a
few placer diamonds were found in streams by others. Some of these
gemstones were even recovered from ant hills along with peridot gemstones. So there is still
much to be found, even with a gold pan.
When
I was a geologist working in Wyoming, I visited hobby dredgers in the Douglas Creek district in the
Medicine Bow Mountains to see what they were finding in their black sands. While
observing the dredgers, I noticed the trout played with their suction hoses as
they kicked up sand, mud, and nutrients: if you want to see a school of fish, you
will always find them around hobby dredges. And it doesn’t take a genius
to realize that when it rains, or during periodic flash floods, or during spring
runoff from snow melt, Mother Nature dumps more dirt and mud into the creek
than a million hobby dredgers could ever. Even so, prospectors are blamed
for environmental damage from naive regulators, whether real or imagined. I
found nearly every regulator in Wyoming was a card-carrying environmentalist group member antipathetic to mining and the American way. Most were not educated in mining operations, and a few objected to anyone stepping on flowers in the national forest.
At
one location on Douglas Creek, a prospector displayed gold in a pan. The gold
was nice, but my eye was drawn to a small, rounded pyrope garnet. Diamond prospectors use pyrope garnets as a guide to diamonds since most erode from kimberlite pipes.
My field
assistant and I had identified some cryptovolcanic structures
upstream from this find on Douglas Creek and we wondered if these were unusual
structures were the source of the pyrope garnets. Cryptovolcanic structures are
circular structures with distinct vegetation anomalies similar to many known
diamond deposits in the region.
Further
upstream, a prospector had recovered two gem-quality diamonds with gold in a
long-tom built in the side of Cortez Creek. The source of these diamonds has
never been identified. At another location in the Medicine Bow Mountains in the
Middle Fork of the Laramie River near the town of Centennial, people on one of
my geology field trips recovered dozens of pyrope garnets in gold pans as they
learned to pan: no gold – just a lot of diamond indicator minerals!
I
never thought I would see the day, but there's been talk of a ban on gold
panning in California. After years of panning for diamond indicator minerals in
streams for research of diamond deposits, the only damage I can imagine is to the gold-panner's stiff knees and lower back requiring periodic trips to a chiropractor. Banning hobby dredging doesn't make much sense, and banning gold pans is like
banning Tonka Toys to keep kids from digging holes in sand piles because of environmental damage. WHY can't we all be reasonable and examine the science (real science, not science fiction) before we open our mouths?
You will never get rich with a pan. A gold pan is simply a tool
to assist in finding the ‘Mother Lode’. The more popular pans are space-age
plastic pans that can be purchased at sporting goods stores. These are a easier
to use than the old tin pans, and the darker colored plastics are good for high-lighting gold.
When you start panning, get comfortable. You might even take off your shoes and
socks, put your feet in the water, or wear water proof boots as you pan, but
find somewhere you can sit down. Be careful that one of the locals (bears) do not sneak up on you. Next, turn on the gold pan switch and check the batteries of your pan (ha, caught you; just kidding, there are no switches).
Placer gold from Gerald Stout recovered on Rock Creek near Atlantic City in western Wyoming displayed in my space age plastic gold pan. |
To
speed up processing, a small shovel is used to dig mud and dirt from the
stream or bank. Stream banks should not be ignored because they are deposited
by the stream – and if gold occurs in the creek, it will also be found in the
bank. It is not necessary to use anything other than a gold pan, but I found a sieve speeds up panning where there is a lot of coarse gravel. When you buy a gold pan, also buy a Grizzly
pan (referred to as a classifier) to place on top of your pan. If you are
in bear country, remember there are two kinds of grizzlies (a sieve, and the kind
that will eat you). In Alaska (and other localities in the West), not only can
bears be a problem, but mosquitoes have been rumored to carry off prospectors, and even drain moose of their blood.
So be prepared for weather and the creatures you might encounter, particularly
when you will be distracted by panning.
Panning
is simple and obeys the laws of physics and fluid dynamics. The specific
gravity of pure gold is 19.3 or 19.3 times as heavy as an equal volume of water;
thus it is notably heavy and will stay in the gold pan as you wash out other
minerals. Many black sand minerals have specific gravities that range from 3 to
6. One of the more common minerals in your black sand is magnetite which has a
specific gravity of 5.2. Because of this, it is also helpful to have a strong
magnet that you can cover with a paper towel or some other material, to run
through the black sand concentrates in your gold pan, especially if you are
looking for gemstones. This is unnecessary for gold because the gold will be
very obvious once you find it. You can learn more about various minerals from a
variety of mineral
identification guidebooks.
Bullwinkle - color pencil sketch by the author. |
When
permeated with water, gravel and soil will tend to behave like a liquid. Stirring
of the dirt in the pan with fingers will assist in sieving. To begin, fill the grizzly
with gravel and place the entire pan under water working the fine-grained
material through holes in the grizzly. Now take out the grizzly and examine
pebbles on the sieve. If there is nothing of value, place this waste material
in a pile on the stream bank (this will be a measure of how much you can pan in
an hour or a day – you will likely be surprised at how little you can pan). The
material sieved by the grizzly should be sitting on the fly screen in the pan.
Work the very fine material through the fly screen.
Some of the many hundreds of since 1977.
|
If the black sands have no apparent gold, start a rhythmic slapping of one edge of the pan with one hand while holding the pan with the other while you still have a little water in the pan. If you have any gold, it will separate from black sand along the edge similar to what is known as a Wilfley Table.
With a 10-power geologists’ loupe, examine the gold. A common mineral mistaken
for gold is mica. Mica has a low
specific gravity (2.7 to 2.9). Even so, it is difficult to get out of your gold
pan and will tend to stay in the pan because of its nearly two-dimensional
crystal habit. It forms flat flakes that cut through water. Many prospectors have
a tendency to let their imaginations run
wild until they get use to seeing gold and mica. While panning, mica will tend
to roll over and over in the water while gold will sit tight.
Pour the water out of the pan, wet your finger with saliva and touch any gold flakes or dust and place them in a tiny vial for safe keeping. Examine the gold either with the loupe or microscope. If you have pristine
Somewhere nearby Oregon Buttes at South Pass in western Wyoming is a giant treasure awaiting discovery.
This old rusty tin gold pan contains many gold flakes recovered from a placer and paleoplacer that some suggest eroded from a belt of granites in the Wind River Mountains 25 to 40 miles to the northwest. This is unlikely. In the center of the photo is a small dish containing cornflake gold that is very jagged and did not transport more than a few hundred yards from its source. The US Geological Survey estimated that, based on the volume of fanglomerates in this area, there could be as much as 28.5 million ounces of gold. The source of this gold remains unknown to this day (photo courtesy of the late J. David Love). |
Using your geologist’s loupe, look for tiny,
equal-dimensional pink, red, orange and purple mineral grains in the black
sands. These may be garnets. If
they are clear and larger than about 4 millimeters, they could be facetable,
particularly by specialized gem cutters in Sri Lanka and India. While searching
for specific kinds of garnets in Wyoming, we found a few hundred anomalies that
produced garnet and other gemstones which eroded from hidden diamond pipes
somewhere upstream. The source of the garnets remains unidentified and suggests
that someone, someday, might find many diamond treasures in the hills of
Colorado and Wyoming.
In one location, near what is
known as the Miracle Mile along the North Platte River north of Sinclair,
Wyoming adjacent to the Seminoe
Mountains, we recovered many pyrope garnets from eroded and hidden diamond
pipes as well as gold in the gravels high and dry and a few miles from the
river. The gold and garnets (and likely diamonds) in this area occur in what
geologists call paleoplacers (fossil stream deposits). The lode source for the
gold likely eroded from gold-bearing veins at Bradley Peak to the west of the
gravels. The source of the diamond indicator minerals remains unknown.
In addition to
possible diamonds in this area, one has to consider where did all of that
paleoplacer gold come from? Did it all come from Bradley Peak in the Seminoe
Mountains? Or did it come from somewhere else. Personally, I like the Seminoe
Mountains. I found several nice specimens of quartz with visible gold in this
area and started a gold rush in 1981 (Hausel, 1995). I also believe that one
creek in this area (Deweese Creek) likely has many nuggets and gold flakes in
it. When I explored this area in 1981 and mapped it later, I could find no
evidence that Deweese creek had been explored.
While looking for the source of
these gemstones, I found a deposit of ruby and pink sapphire at Palmer Canyon west of Wheatland.
This deposit also had other gems that included thousands of carats of sky-blue
kyanite and blue to purple iolite
(water sapphire).
Over the next few of years, I found
a half-dozen ruby deposits, a giant
iolite and kyanite deposit at Grizzly Creek, iolite at Ragged Top Mountain
and also at Owen Creek in the Laramie Mountains and a deposit with millions of
carats of kyanite. Some of the iolite at Grizzly Creek weighed many thousands
of carats. One I carried in a backpack weighed more than 24,000 carats – the
largest ever recorded. But much, much larger iolite gems were left in the
outcrop!
The Orange River of southern Africa is well
known for placer diamonds, as are some localities in Brazil. In North America, there has
only been a few placer diamonds reported outside of California. But based on the
many diamond indicator minerals found in Colorado and Wyoming (as well as
120,000 diamonds mined from kimberlite rock) and the more than 100 kimberlite
pipes in this region; it is surprising that more stream-deposited placer
diamonds have not been found. The largest reported placer diamond from this
region was 6.2 carats found in Fish Creek on the border of Colorado and Wyoming
south of Laramie. The largest diamond found in a kimberlite in this region
weighed 28.3 carats.
Vein (lode) deposit seen in back (roof) of mine in California.
|
Not
long after the North Carolina discoveries, gold was found in Georgia. A gold
rush in Dahlonega in 1829 resulted in as many as 500 gold placers and lode mines.
Many nuggets were recovered including those of 54, 42, 40, 35, 26, 25, 19, 18,
15, 11, 6, 5, 4, 3 and 2 troy ounces. These were found in Gilmer, Habersham,
White, Cherokee and Lumpkin Counties.
Alaska
has been a good source for nuggets. The largest was discovered in 1998 in Swift
Creek near Ruby in central Alaska. The softball-size nugget, known as the
Centennial nugget, weighed 294.1 troy ounces. Another large nugget found on Long
Creek near Ruby weighed 46 ounces. Large nuggets were also found on Anvil Creek
near Nome in western Alaska that included nuggets of 182, 107, 97, 95 and 84
troy ounces.
Nuggets from the Kuskokwim Mountains in Alaska: the largest is about one troy ounce. |
Another nugget, known as the Chicken Nugget,
was found in Wade Creek near Chicken in eastern Alaska in 1983. This weighed
56.75 ounces. A nugget of 56 ounces was found on Dome Creek near Tolovana in
central Alaska and a 52-ounce nugget was found on Lucky Gulch (Valdez Creek)
near Denali in central Alaska.
In
the Weaver Mountains, samples of quartz with visible gold are often found with
nuggets. Gold in the nearby Bradshaw Mountains has been found in Lynx Creek,
French Creek, Big Bug Creek, and the upper Hassayampa River. Based on the
geology and location of gold nuggets found in Arizona, several gold deposits
have likely been overlooked.
Large
nuggets were mined in Montana at Alder Gulch and California Gulch near
Phillipsburg in the southwestern portion of the state. In 1902, a football-size
nugget of 612.5 troy ounces was recovered from California Gulch. This was
followed by discovery of a 77 troy ounce nugget from the same gulch. The
largest nugget found in Colorado weighed 160 troy ounces and was named Toms’
Baby found in 1887 on Farncomb Hill at the head of the French Gulch placer near
Breckenridge.
The
largest nuggets found in the US were from California. At Carson Hill in
Calaveras County, a nugget weighing 2,340 troy ounces was recovered in 1854.
Another water worn nugget of 648 troy ounces was found at Magalia, California
in 1859. Both of these were too large to have transported any distance.
The
largest nugget from Wyoming weighed 34 ounces. There was an very interesting
reference to a boulder in Rock Creek at South Pass that contained an estimated
630 ounces of gold. If so, this nugget with attached quartz was likely the size
of a football. Many nuggets were also recovered from Carissa Gulch.
So
as you are looking for gold and other treasures with a gold pan, keep in mind how
valuable gemstones can be. Gold is very valuable, but some pink and red
diamonds have sold for as much as $1 million per carat. A carat is tiny
compared to an ounce of gold and some of these diamonds have sold for many
thousands of times the value of an equivalent weight in gold.
Gold pan concentrate after all of the light-colored minerals panned out leaving primarily magnetite, gold and garnet with a
few, uncommon zircons (Douglas Creek, Wyoming).
References Cited
Erlich, E.I., and Hausel,
W.D., 2002, Diamond Deposits – Origin, Exploration, and History of Discoveries:
Society of Mining Engineers, 374 p.
Hausel, W.D., 1994, Economic
geology of the Seminoe Mountains greenstone belt, Carbon County, Wyoming:
Geological Survey of Wyoming Report of investigations 50, 31 p.
Hausel, W.D., 1996, Pacific Coast diamonds-an unconventional
source terrane in Coyner, A.R., and
Fahey, P.L., eds., Geology and ore deposits of the American Cordillera,
Geological Society of Nevada Symposium Proceedings, Reno/Sparks, Nevada, p.
925-934.
Hausel, W.D., 1998, Diamonds and mantle source rocks in the
Wyoming Craton, with a discussion of other US occurrences: Wyoming State
Geological Survey Report of Investigations 53, 93 p.
Hausel, W.D., 2001,
Placer and Lode Gold Deposits: InternationalCalifornia Mining Journal, v. 71, no. 2, p. 7-34.
Hausel, W.D., 2006, Minerals & Rocks of Wyoming, A Guide for Collectors, Prospectors and Rock Hounds, WSGS Bulletin 72, 125 p.
Hausel,
W.D., 2009, Gems, Minerals and
Rocks of Wyoming. A Guide for Rock Hounds, Prospectors & Collectors. Booksurge, 175 p.
Hausel,
W.D., and Hausel, E.J., 2011, GOLD - Field Guide for Prospectors and Geologists - Wyoming Examples. CreateSpace, 366 p.
Hausel, W.D., 2014, A Guide to Finding Gemstones, Gold, Minerals and Rocks: GemHunter Books, 369 p.
Hausel, W.D., 2014, A Guide to Finding Gemstones, Gold, Minerals and Rocks: GemHunter Books, 369 p.
Hausel,
W.D., and Sutherland, W.M., 2006, World Gemstones: Geology, Mineralogy, Gemology & Exploration: WSGS Mineral Report MR06-1, 363 p.