Finding Carats, Carrots, and Karats | Searching for Gold and Diamonds

When some think of gold, the word karat may come to mind. Or is it carrot or maybe carat? So did I just pan a vegetable, a piece of gold, or a diamond from that stream? 

Schematic cross section through an ideal kimberlite
pipe showing carrot-shaped diamond pipe. Generally,
the vertical column from the blow to the maar is
about 5,000 feet. The blow is the enlargement at the
base of the pipe, and the maar is the volcanic orifice.

If you are a rabbit, possibly you were hoping to pan a carrot - but then again, you wouldn't be reading this blog. Carrots are good sources for vitamin A and good for attracting rabbits. 

I tried my green thumb in Gilbert Arizona last summer and planted carrots only to discover few edible things grow in the Phoenix valley in the summer (other than prickly pear cactus - and its questionable if many of us would try to peel the skin off the cactus just to eat the slimy plant). All of my carrots deep-fried in the ground as temperatures soared into triple digits for a month. 

I still have difficulty adapting to Arizona’s hot weather after living in Wyoming much of my life. But someone told me the other day that Arizona is like Wyoming, just in reverse. People just don’t go outside when temperatures hit -50^oF in Wyoming (although I always skied to work when temperatures fell below -30) and they don’t go outside when temperatures rise above 110^oF in Arizona. I never thought of it that way. But at least in Wyoming, my Nissan truck had a heater; in Arizona it doesn't have an air conditioner (didn't need one in Wyoming). One day I'll have to break down and buy a new truck with AC.

Carrot comes from the French carotte that refers to the favorite food of that old "wascal wabbit". It has nothing to do with the other two homonyms carat and karat; except that diamond exploration geologists like to use the shape of a carrot to describe what the cross-section of a diamond pipe (kimberlite volcano) might look like, but this is as close to diamonds a carrot gets.

One of the more than 300 cryptovolcanic structures discovered in the Colorado-Montana-Wyoming kimberlite
 (diamond) province (Hausel, 2014). This depression is filled with water in the spring, but has an unexplained
 vegetation anomaly, enriched carbonate soils. The anomaly is circular and characteristic of many diamond
 pipes in the Colorado-Wyoming State Line region.

Diamond pipes are largely carrot-shaped because they erupt with large amounts of highly pressurized gas and shoot out of the earth's mantle like a shotgun blast producing a maar-like volcano. When the kimberlite magma breached the earth’s surface, the eruption was explosive with magma ejected with country rock boulders and highly pressurized gas (water vapor and carbon dioxide). Some researchers suggest gaseous emplacement velocities could have been as rapid as Mach 3. 

Distinct depression associated with a diamond pipe in Colorado.
The diamond pipe sits under an open, grass-covered park.
Many kimberlites lack tree growth and often give people an
impression of an impact crater. This cryptovolcanic structure
was trenched and diamonds along with kimberlite
were recovered at shallow depth. Also note the fault trace marked 
in red. As a prospector, you should always walk these traces out
as far as they go simply because more than one kimberlite often
erupted along the same fracture. This is how I discovered some 
kimberlites in this region that were missed by others.

So much carbon dioxide was present in these eruptions that the EPA would have issued a citation to Mother Nature for releasing these toxic(?) fumes. (In 2009, Obama’s EPA listed carbon dioxide as an air pollutant. Prior to 2009, carbon dioxide was just a simple gas or plant food used by all plants, algae and many forms of bacteria needed to produce organic compounds and release the oxygen we all breathe [you know its coming, Obama will likely tax us for using oxygen]. It's good our government is watching out for us, otherwise we would not have been aware that such an important gas required for life was a pollutant).

Kimberlite (diamond) pipes (unless deeply eroded) have circular expressions in plan. This expression often looks like an impact crater. To see some very impressive diamond pipes, I recommend searching the Internet for “Ekati Airport, NWT” to see Canada’s premier diamond mining operation. Now search for the “Big Hole Kimberley, South Africa”. This is another diamond pipe that was operated years ago and looks like an impact crater. Search throughout the Kimberley city limits and you’ll find other diamond pipes. 

Now take a look at Russia. Search for “Mir Mine, Russia” also known as Mirnyy Diamond Mine. This will take you to one of the more impressive circular pipes. While you are looking at these areas, remember kimberlites almost always occur in clusters and often line up on linear fractures. In these three areas, you may find other circular anomalies that have not been mined that are likely kimberlite pipes.

In addition to finding the circular to roughly circular depressions, one needs to look for other characteristics, such as a group of circular to elongated depressions lining up on some kind of lineament. For example, take a look at the Lost Lakes in the Red Feather Lakes region of northern Colorado. You will find a group of lakes and depressions that sit on a distinct linear fracture that trends about N30oE. And when you take a look at the lakes along the northeastern extent of this fracture - wow - the lake shores look like they are coated with salt or blue ground. Several years ago, I visited these anomalies, and the soils are very carbonate rich - if you drop some dilute HCl acid on the soil, it will fizz. The country rock in the region is mostly granites and amphibolites which do not have any known carbonate. Now these are excellent cryptovolcanic structures and possible kimberlites. 

Years ago, I also came across a cluster of depressions in the Indian Guide district of Albany County Wyoming. All of these are situated along N-S to northwesterly fractures immediately west of the Iron Mountain kimberlite district, where dozens of kimberlites (including a couple of diamonds) were found years ago (Hausel and others, 2003). I tried to get the State to provide me with a grant to drill these, but to no avail. The state was much more interested in providing another agency with money to see how high a rare and endangered jumping mouse could jump (it turns out this rare mouse was not so rare after all - just a normal field mouse that was startled). So these cryptovolcanic structures remain  unknown as to why they exist - but the fact they are sitting along the western trend of the Iron Mountain kimberlites strongly suggest Wyoming is losing its marbles, or should be say, carats.

Now take a look at the Twin Mountains Lakes area near Cheyenne. I identified more than 50 interesting structures (depressions and lakes) in this area that are situated in a distinct regional fold in the Proterozoic amphibolites that could be an extension of the State Line kimberlite district. Some appear to be very large - could these be kimberlites?  No one has ever drilled or sampled these and they look like good targets to me. 

Now take a look at the Kelsey Lake kimberlites in Colorado. These were mined for a short time and produced many high-quality gemstones including a 28.3-carat diamond along with a diamond fragment from a stone estimated to have been about 80 to 90 carats (Hausel, 1998, 2014). As you examine Kelsey Lake, keep in mind this was at one time a diamond mine (1996) and there are at least two reclaimed kimberlites and much of the diamond ore was never mined due to legal problems. Also note there is still fresh blue ground exposed in the reclaimed area. In this region, there are also several unmined kimberlites - I know, because I mapped them years ago. They are all located in my new book.

Now here is something you want to really think about! The Kelsey Lake kimberlites sit right on the edge of Fish Creek and a small tributary to the south of the pipes. These streams must be filled with diamonds! In southern Africa, it was noted diamonds from the Kimberley region were transported more than 600 miles in the Orange River to the coast of western Africa. Now imagine where could all of those diamonds that eroded from Kelsey Lake be. Personally, I would map out Fish Creek and follow it and associated drainages for at least a hundred or more miles down stream.

Gem-quality diamond indicator minerals from the Sloan kimberlites, Colorado

Diamond indicator minerals (chromian diopside to the left and pyrope garnet to the right) in Sloan kimberlite specimens.

When one diamond company was taking samples for kimberlite in this area, they recovered a group of diamonds including a 6.2 carat gemstone in Fish Creek near Kelsey Lake - and they were NOT even looking for placer diamonds. 

Recently, I was notified by a prospector who read my book on Finding Gemstones, that he panned out a cache of diamonds including one just under 5-carats in weight out of a stream I had identified that would be an important diamond placer. Remember, tiny diamonds are almost worthless (as the boys on Gold Rush discovered in South America). But large gemstone diamonds can be valuable. 

If you decide to search the area for diamonds, there is a lot of private property, but also remember a couple of other things: (1) Fish Creek is long, (2) gem-quality diamonds can survive stream transport of at least 600 miles, (3) kimberlites yield other gemstones known as diamond indicator minerals, and (4) the State Line kimberlites have been eroded off and on for the past 600 million years and the largest portion of the kimberlite pipes (the mouths) have been eroded and the diamonds carried downstream (see the schematic cross section through a kimberlite above). It has been estimated that 2000 to 3000 feet of vertical column of kimberlite pipe in this area has been eroded. So, what are you waiting for?

The Carat

The carat may not be enriched in vitamin A, but if large enough, some carats can by a lot of carrots and vitamin A. A carat is what is used to measure the weight of gemstones. One carat equals only 0.0066 troy ounces, or 0.2 grams (200 mg). If you have a troy ounce of gold, this is equal to 31.1 grams or 155 metric carats (152 troy carats). Periodically, jewelers speak in terms of points and there are 100 points in a carat and each point equals only 2 mg (milligrams).

A flawless, 1,720 carat iolite gemstone I found at
Palmer Canyon Wyoming with some sapphire, ruby, and kyanite
gemstones - now that's a lot of carats. 

Now, if you have one troy ounce of gold worth about $1800 and compare this to a rare, pink, Argyle pink diamond worth about $1,000,000 per carat (unfortunately, I don’t have any Argyle Pinks), you will get a good idea at the incredible value of some gemstones. A one-carat rare pink diamond could be worth about 150 times more than a equivalent weight in gold! Not bad for a little crystal.

So where do pink diamonds come from? The pink in diamonds is thought to be the result of shear stress on the diamond, and such gems are thought to form at depth in a subduction zone unlike other diamonds mined in most kimberlites. The great majority of pink diamonds have been mined along the northern coast of Australia at the Argyle mine. To see this mine on Google Earth, search for “Argyle Lake, Australia” and the mine is a short distance southwest of the lake. Very recently, the largest pink diamond ever found was recovered from the Argyle mine. Described by many news outlets as a giant diamond, this one is only 12.76 carats (probably around 12 to 14 millimeters across or a little more than a half inch). As a comparison, the largest diamond ever found was the Cullinun that weighed 3,106 carats). But because of its rarity and color, the Pink Jubilee diamond may sell for as much as $10 million. When cut and polished, it will of course be even smaller.

A group of very expensive Argyle fancy diamonds on display at the
Argyle mine in Australia. I asked, but they wouldn't let me have
any of these.

The Karat

Now let’s look at another word that sounds like the other two words - the karat. Karat also has little to do with rabbits and vitamin A unless you purchase a gold pendant in the shape of a rabbit. Karat refers to purity of precious metals in jewelry. 

When you recover gold in the nearby mountains, it could be nearly pure, yellow gold or could be not quite as pure brassy electrum. Natural electrum refers to a mixture of gold and silver (>20% silver) that is sometimes referred to as white gold.

Natural gold (or precious metals in general) is alloyed with other metals including silver, platinum, palladium, copper, nickel and other metals. It is seldom pure (99.9%) and must be purified to produce the golden metal with few alloys. The purer the gold, the more malleable, soft, heavy and noble (resistant to oxidation and corrosion) is the metal.

Gold from Rock Creek Wyoming mined a short distance downstream from several gold-bearing lodes. This gold is a little whiter (brassy) than gold from some other nearby localities and likely has some silver. Some gold in this area was tested and found to contain as much as 11% silver.

The Rock Creek placer mine was closed by a 1942 War Minerals Board order. This suggests that the World War II miners were recovering gold worth $34/ounce at a profit. Today, gold prices are 50 times higher. Thus this placer likely is still minable. To visit this placer on Google Earth, search for “Atlantic City, Wyoming”.  Atlantic City sits in the upper part of the Rock Creek placer and is the place I figured I would have retired and ending up working for the Prospecting and Mining Journal - but things didn't quite work out that way. Now instead of shoveling tons of snow, I'm basking in the sun.

There are many other placers in this region that contain minable gold. One may be Willow Creek that runs through South Pass City. Willow Creek has a relatively small volume of gravel, but its location (cutting across the Carissa lode, the principal gold-bearing lode in the district) guarantees it will have rich pay streaks. However, Willow Creek was closed to mining by the Wyoming Department of Environmental Quality due to the toxic levels of mercury (whether imagined or real). During my research of this region over a seven year period, I did not find any evidence of primary mercury in the district and the possibility of large quantities of mercury being dumped in the creek by 19^th century miners is unrealistic. Mercury was a valuable commodity in the 19^th century. If some mercury were actually lost in the creek in the 19^th century, it would have been a very small, finite source and mining would only serve to clean the creek bed. 

Pure gold is designated as 24-karat by jewelers: 24-karat gold being the purest at 99.9% gold that is also referred to as 0.999 fine. Being essentially pure, 24-karat gold is soft and can be difficult to some jewelry applications where a wearer of the metal has an active life style. This is because the malleability of pure gold insures such jewelry will be easily scratched. Gold purity can be defined by the formula:

P_{(karat weight)} = 24 x M_pg/M_t (mass of pure gold /total mass of the material).

It is defined that there are 24 units (24 karats). Thus if you could find jewelry of 1-karat purity, it’s would not be something to brag about. One-karat would mean such jewelry is made up of an alloy of 1 part gold and 23 parts alloy metal(s). The percentage of gold in 1-karat would be determined by dividing 1 by 24, which is equal to 0.0416666. Rounding off this number gives 0.042, which is the fineness. To get the percentage of gold in 1-karat simply multiply fineness by 100 to get 4.2% gold.

Yellow gold from Smith Gulch at South Pass, Wyoming.
Two prospectors recovered 20 ounces per week
while prospecting Smith Gulch in the 1980s using
a small backhoe and a trammel. And keep in mind, this was
a placer that supposedly had already been mined out. 

Some jewelry is listed as 18-karat gold (18/24=0.750 fine). This consists of 75% gold. Another common mixture is 14-karat gold (14/24=0.583 fine) (58.3% gold); and 12-karat gold (12/24=0.500 fine) (50% gold).

12 karat gold = 12/24 = 0.500 (fine)

0.500 x 100 = 50%

Metals often alloyed with gold include nickel, copper, palladium, manganese, silver, zinc, aluminum, iron, gallium, indium, ruthenium, platinum, palladium and rhodium. By using various alloys, gold can be hardened or it can change color.

Using nickel and silver will give gold a subtle white appearance to yield white gold. The nickel provides not only white color, but gives the noble metal strength. However, some people are allergic to nickel. In this case, palladium, platinum, or rhodium can be used to substitute for nickel in white gold. Platinum-group metals are inert just like gold and will not produce allergic reactions (but they cost a lot more than nickel).

Rose and pink gold is formed by using copper as an alloy. The more copper, the deeper the pink color. The use of copper was popular in Russia in the past and this became known as Russian gold, which is now archaic, but the term still persists in the literature. Rose gold is 18-karat gold with 25% copper. Red gold is 12-karat gold (50%) with about 50% copper.

By adding zinc, one can produce less malleable and harder gold. Cadmium can be used to produce green gold. Other varieties include black, purple or blue gold. Purple or amethyst gold is a mixture of gold and aluminum that is 18-karat and brittle. Blue gold is produced by adding indium or gallium to 12- or 14-karat gold. By adding certain metals to gold, the gold can become more and more brittle, more corrosive, and may even discolor in contact with skin.

So karat is not a vegetable, but instead a measure of purity. If we were to weigh gold, the precious metal is weighed in ounces or measured in grams. But, then there is an ounce, and there is an ounce.

When is an ounce an ounce?

Weighing precious metals has caused considerable confusion. This is because there are two different ounces and few people indicate which ounce they are dealing with and not everyone uses the proper ounce for weighing precious metals. Most have the impression there are 16 ounces in a pound. Well, this is true when you are weighing something besides precious metals. The avoirdupois ounce we see on our bathroom scales when we weigh ourselves in the morning is the unit used to weigh objects in most English speaking countries. It comes from the Old French aver de peis which is interpreted to mean weight of goods. So how much your goods weigh in the morning is a result of how much indulgence you had during the previous night.

A 24 ounce gold nugget from Rock Creek Wyoming. 

The weight of precious metals is reported in troy ounces. The troy ounce was part of the Roman monetary system and many assume it refers to the city of Troy of the ancient Roman Empire. But it is instead named after the city of Troyes, France. The troy ounce is different from the avoirdupois ounce and equal to 20 pennyweights (another weight measurement used by prospectors). There are only 12 troy ounces in a troy pound and it takes 1.09714 avoirdupois ounces to equal a troy ounce. A troy ounce also has 31.1 grams while the avoirdupois ounce has 28.35 grams. There is a great website that does all of these conversions for you: 

The fire assay furnace at the Vulture mine, Arizona. Yes the assay house needs a little cleaning.

Gold has been prized since earliest times. Intricately sculptured objects and jewelry have been found in tombs in Iraq and Egypt where Jason and the Argonauts searched for the Golden Fleece. In Biblical times, placer miners used sheep fleece to capture gold in primitive sluices; thus this was the prize sought by Biblical Jason. Gold’s rarity is one reason why the metal became a symbol of wealth and power. The rareness of gold is due to it being formed during supernovae explosions when enough energy and pressure are possible to fuse atoms together to form gold. Without exploring stars (and likely the big bang) we would be without gold.

References:

Boyle, R. W., 1987, Gold – History and Genesis of Deposits: Van Nostrand Reinhold Company, 676 p.

Erlich, E.I. and Hausel, W.D., 2002, DiamondDeposits – Origin, Exploration and History of Discovery: Society of SME, 374 p.

Hausel, W. D. and Hausel, E.J., 2011, Gold –Field Guide for Prospectors and Geologists (Wyoming and Adjacent Areas): CreateSpace, 365 p.

Hausel, W. D. and Sutherland, W.M., 2000, Gemstones and Other Unique Minerals and Rocks of Wyoming – A Field Guide forCollectors: Wyoming State Geological Survey Bulletin 71, 268 p.

HEY, there are many OLDER posts - be sure you look at them

Professor Hausel's Guide to Gold

Be careful of legends! The Superstition Mountains!
Many gold legends are nothing more than legend. Wonder
why no one ever found the Lost Dutchman mine? Well,
maybe there's a mine out there, but why bother when there 
are plenty of known gold mines around the West.

You've probably heard it said before. "Gold is where you find it". Not sure what wise guy came up with that saying - but its true even though it should be obvious. But the problem is finding the location of the "where you find it".  

 I think I have a nose for finding gold deposits and its not as hard as some make it out to be. Some years ago, a group of 7 geologists (including me) was awarded the Thayer Lindsey Award for making a major gold discovery, and prior to that acknowledgement, I was presented the 2004 Distinguished Service Award for the many other gold, diamond, colored gemstone, base metal and similar discoveries. It's not that I'm that good of geologist, its just that I follow up on leads - anyone with a decent geology education could do the same.

Here are some suggestions for finding gold:

(1) Use science (unlike the CDC). Sounds pretty straight forward, but it is amazing how many promoters and scam artists swear by using unscientific methods such as dowsing, witching sticks, legends, wet dreams, feelings, legends and even fraudulent information to find gold (sort of like the democratic party). None of which will work.

The iron stained (gossan) at the Vulture gold mine, Arizona.
Learn what you can about veins and how to follow them
if you want to find gold. There will be many false trails, but
some will be good. Just don't give up!

When I was at the Wyoming Geological Survey, I had one dowser who would read my ICMJ prospecting and mining journal articles and would dowse the paper and ink maps in each article, sketch a couple of pencil lines and then send me a copy of the article to tell me where the mother lode was on each paper map. This went on for a few years and I finally lost touch with him, so he was either recaptured by the authorities, or went to work for the Biden administration. I'm not sure why manipulating ink on cheap paper would allow one to find gold - but that's the kind pseudoscience that some of these guys used.

Another dowser would send me advertisements for his school of dowsing (all hand written) for a variety of courses - each class sounded like and episode of the Twilight Zone. One of his better ones (I tried to get the University of Wyoming to pay for my registration) was how to find lost dogs and other pets with a dosing rod while flying over the country in a 747. Now if you don't laugh, you should see a professional. Not sure if it was me, or my job that attracted these guys - but I must say, I did actually enjoy hearing their stories, and I'm sure I will get lots of people who would like to debate the science of dowsing, but for me, I've seen enough. Yes, I've seen people use dowsing rods and watch the stick swing up and down as they walk, but I've never seen anyone find anything more than sagebrush or dirt with dowsing rods. 

Gold nuggets from Arizona

Then there was 'Barbara' - a little old lady prospector/con artist/democrat from Atlantic City Wyoming who knew where all of the gold was! In other people's wallets. Barbara was well-known for her scams - and yes, at one time she was the chairperson of the Wyoming democratic party. 

She was only about 97-pounds soaking wet, chain smoker, serious drinker, and actually entertaining. She once sold a tourist a jar full of gold at a reduced price. He was so excited to show everyone his jar of gold at the Atlantic City Mercantile, until he discovered he had paid more than $5000 for jar full of worthless mica. Within a few days, the Atlantic City volunteer fire department responded to a fire.  Barbara's old Cadillac was ablaze.



Visible gold in rhyolite from Arizona. When you see this
much gold - you struck it rich. A rule of thumb. If you see
one tiny spec of visible gold on a rock sample, it will assay
close to 1 ounce per ton. A rock with this much gold likely
would assay 100 ounces per ton.

On another day, Barbara latched on to a well-dressed tourist from Missouri who stepped into the Atlantic City Mercantile to ask directions. Barbara sat down with the unsuspecting visitor and did her best to sell him the Mary Ellen gold mine  south of town, until he told her he and his son Steve, actually owned the Mary Ellen mine. 

Then there was a University of Wyoming geology professor. Now this one really took the cake! The professor wrote on UW letterhead paper that 297,000,000 ounces of gold reserves existed and had been identified at Pine Mountain west of Casper, near the Rattlesnake Hills. The only problem, no gold had ever been identified at Pine Mountain even though it has been a popular site for mining scams similar to the South French Creek area in the Medicine Bow Mountains. After this professor and others were investigated by the secret service, no charges were files as no money had yet exchanged hands - so the university promoted the professor.

One way to learn about gold is to read some good gold prospecting books. Then find a gold district near your town you can visit (don't buy and jars of gold) and get out on some mine dumps and start examining the area around the old mines. Look for any lineaments such as narrow quartz veins running towards the old mine dump you are standing on and walk along this vein. If there area lots of prospects on the vein, this start looking at the vein and learn all you can. See if you can follow the vein for a few hundred feet, a few thousand feet. 

The color of natural gold is impressive. These gold flakes from the Dickie Springs paleoplacer
gold deposit in Wyoming, have very high specific gravity. As you swirl water in your pan, these flakes
 will be difficult to move (unlike mica). Mica will seem to stay in place as you swirl water in your
pan, but when you look close, mica tumbles in the water because of low specific gravity.

You might also look for linear depressions. These could be related to faults or shear zones. See if there is much in the way of prospects on these depressions. If there are, it is likely an old mineralized shear zone.

(2) Learn what gold looks like. This is important. Visit museums, look at photographs in books and on the Internet. Usually, the only thing that is mistaken for gold is pyrite and mica and sometimes chalcopyrite. Most people mistaken mica for gold - like Barbara's friend at the Atlantic City mercantile. Years ago, I wrote an article for the ICMJ about a prospector in Centennial Wyoming who had been jumping someone else's mining claim on the Middle Fork of the Little Laramie River all winter long. His name may have been 'John', but he used different aliases when talking to me. Anyway, he mined all winter using snow shoes to get to the claim and recover all of the gold he could, hopping not to be discovered. He told me he accumulated a few barrels filled with gold in his single wide trailer at Centennial. Finally, he brought in a couple of Ball jars filled with the material to verify his riches. You could see the disappointment when I told him he had some high-quality planting soil, but no gold.

Visible gold in quartz and hematite, Carissa Mine,
South Pass, Wyoming

(3) Visit old mining districts. Read about the old mining districts you visit and keep in mind a couple of things - legends are just that - they are legends often concocted by an old prospector in a bar in the past after having one too many drinks. So why waste your time on some one's past drunk when there are still plenty of gold deposits to be found. It is extremely rare (actually rarer than getting the truth from a politician) for any gold mine to be mined out. Gold miners always leave a lot of gold in the mines and in the veins that they mined along. At one time not so long ago, gold prices were only about $18/ounce, then about $20/ounce and then $35/ounce. Just the other day (1/17/22), they were $1,824/ounce. 

When gold prices are low, miners only mine high grade material, typically material that assays better than 0.2 opt Au. Today, some companies mine gold ore at an averages of only 0.01 to 0.02 opt (ounces per ton) and better. So, the past miners left all of the low-grade gold ore and often missed a lot of high-grade gold ore. Think about it, how many times have companies gone back into old mines or old districts and began mining in an old mine. New mining districts are rarely found, so stick to the mining districts until you have a lot of good experience.

It is worthwhile to visit old gold mines that made a profit prior to the War Production Board closing all gold mines in the US in 1942. Many of these mines never reopened after the second world war for many reasons, but these were commercial mines at a low gold price. At today's gold price, which is about 50 times greater than when these mines closed, these should be viable.  Also, search the old US Bureau of Mines publications on mining districts. The Bureau of Mines was an excellent and pragmatic group of geologists, engineers and chemists who were mostly fired from their jobs after producing extremely valuable material on mines, exploration, mining, recovery, etc. simply because of the Clinton Administration who objected to their scientific data - i.e., it wasn't green. Politics like this destroys people's lives and does little to help anyone (other than multi-millionaires like Clinton and Gore).


Giant King gold mine, CA. Note the iron stained (gossan) in the blue serpentinite. Some serpentinites have gold, some platinum and palladium, some will have nickel, and in California, some may have gemstones of benitoite or sapphire.

Gold Processing & Extraction While Bear Hunting

Visible gold in goethite and quartz,
Mary Ellen Mine. (Steve Gyorvary specimen).

If you decide to mine lode gold, you can keep it simple and dig for specimen-grade gold samples from veins and breccias. Although such samples with visible gold are rare and more valuable than the price of gold, if you have the right vein or ore shoot, they are worth pursuing. When ever you see gossans or tawny to brown limonite and goethite in quartz - look for visible gold! Gossans are something prospectors need to learn to recognize. 

If you decide to mine your lode using open pit or underground methods - you will need deep pockets to pay for mining as well as permitting. In this case, it may be easier to start looking for a company that has the expertise and deep pockets.

Detrital gold is by for the best type of gold to search for as a prospector as it has already been mined by Mother Nature, and now it is up to you to figure out how to concentrate it. To extract placer (detrital) gold from a creek using a gold pan (not recommended as it will wear out your back), sluice, trommel, dredge or some other concentrating equipment, you will likely need permits from the State or Feds. The government is totally out of touch when it comes to permitting, as in most cases they will try to permit you to death. Some states may even require a permit to operate a gold pan on public property even though this would be as absurd as requiring a permit to operate a fork in a restaurant; however, Democrats were actually talking about this when I left Wyoming. One of the easiest ways to find out rules and regulations for prospecting in your state is to join a local prospecting club. Many gold prospecting clubs are associated with the Gold Prospectors Association of America: and there are independent groups such as the Wyoming Prospectors Association. 

GRIN AND BEAR IT! And don't forget to support the NRA, unless you are willing to prospect grizzly country without a gun. Just imagine, panning in Wyoming, Montana, Alaska or even Washington DC and you look up just in time to see a grizzly licking its chops while staring at you 50 feet away. Sure, you can use that brand of bear repellant spray your university professor recommended even though he/she/it has never seen a grizzly except on TV. 

In the woods, a bear can easily sneak up to you, particular when it sees you are listed in the specials on the menu. Remember, it can charge as fast as 35 mph! But, you have that handy, dandy spice, errr, repellant in your pocket or back pack. How fast can you get that vial out of your back pack? "Oh, there it ...." "CHOMP".  

If you are lucky, you may have a little more than a second to get that thing out of your pocket, get the cap off, point and squirt, but I'll bet you end up served on the dinner special. That 700 to 1,500 pound grizzly can cover a short 50-foot distance in .... can you believe 1 second! Don't believe me, you can do the math yourself. And if you are lucky enough to point and shoot your little spice vial. I imagine that  bear mass, with all of its kinetic energy, is not going to stop easily - "splat and chomp!" 

So, the next time your hike and bike Berkeley professor tells you to use repellent, remember he/she/it is thinking about human sacrifice to keep the bears well fed. But if you have a gun, particularly a very large gun (12 gauge), 44 or 45 cal., you may stand a chance. But, why not a 357 magnum? Well, because one of our geologists in Alaska shot a typical, everyday, meat-loving black bear in-between the eyes at point blank range as it was trying to eat another geologist. All it did was give the bear a nasty headache. It knocked the bear down, but then it got up, and ran off until the next day, when it decided to come back looking for another geology snack.

GOLD PANNING POLLUTION. When I was in Wyoming, there was a faculty member in the  Geology Department who thought gold panners were polluting Douglas Creek in the Medicine Bow Mountains. Obviously, she never tried to operate a gold pan herself, otherwise she would not have made such a ridiculous statement.  Gold panning is a real, serious, pain in the neck (as well as the back and especially, the lower back). 

Gold Panning in the Medicine Bow Mountains, Centennial
Ridge district. No one found gold at what was known as the
Mother Lode, but some found nice specimens of pyrite
(fool's gold) and some found almandine and pyrope garnet!
Pyrope garnet is a tracer mineral for finding diamonds!
So, somewhere upstream there is an eroding diamond pipe
leaking pyrope garnet (and maybe diamonds) into the creek.

Years ago, I met two prospectors from Lander Wyoming who were working Smith Gulch at South Pass while I was mapping the greenstone belt and old mining districts, and they were recovering about 20 ounces of gold per week. At 1600/ounce, that's only about $32,000 per week. Not bad for two guys.

Often we get use to seeing gold pans filled with gold - this does not really happen in real life; so when we see gold filled pans, remember, the gold was found with some other equipment and placed in the pan for a photo opt.

Panning is an easy - it just takes a little confidence and a couple of pans full of sand and mud, and soon you will be an expert. Gold has a very high specific gravity (15 to 19.3), which means you are going to have to make an serious effort to wash gold out of your pan. So put a little effort into your panning. If you are ending up with a tablespoon or two of what is known as black sand (mostly magnetite with a few minerals such as ilmenite, zircon, etc), with specific gravities around 4 to 5, you are doing good. But be assured, you probably did not wash out much gold as it is 3 to 4 times heavier by volume, than those black sands. 

Stamp mill at Goldfields, Arizona

While panning for diamonds in California, we recovered a gemstone known as benitoite near Poker Flat and chromian diopside from serpentinite in northern California (Hausel, 1996). In Wyoming, we panned many gem-quality garnets, some diamonds, and numerous sapphires and rubies and found dozens of localities where gold had not been reported before (including the Laramie City landfill!) (Hausel and others, 1994). In samples panned in the Laramie Mountains near Vedauwoo, we found fluorite (easy to recognize in black sands - it is purple in this area and crushes easily) and many samples with chromian diopside and pyrope garnet near Eagle Rock. This suggests there are undiscovered diamond pipes! 

While searching for evidence of diamond pipes, we found distinct, small, structurally-controlled vegetation anomalies including one at (41o17'39.96"N; 105o22'46.95"W) along the edge of Eagle Rock. This same area has several beaver ponds to the northwest, any of which could be hiding diamond pipes.

Not too far from Eagle Rock, we identified other possible diamond pipes that remain a mystery. These included the Bowling Pin Anomaly (41o11'15.39"N; 105o19'34.67"W), a circular depression with carbonate in soils that had a couple of bowling pins in the depression. The entire area has many such anomalies including the HJ17 depression (41o12'01.92"N; 105o19'10.46"W). Further south (actually just south of the interstate) we identified 42 highly suspicious cryptovolcanic structure of which anyone of them could be a kimberlite (diamond) pipe. All of these anomalies remain untested due to various access problems.

Arrastra gold concentrator. This was a very primitive grinder with large rocks
attached to a pivot at the center. A mule would walk around in circles pulling
a lever that would continue to drag the boulders over a trough where gold-
bearing quartz would be placed to be crushed.

Other minerals of interest found while panning include a lot of white material that was impossible to pan out. It was too heavy! So I stuck it under a black light and with short-wave ultraviolet light, it exhibited strong, blue fluorescence - it was scheelite (a tungsten ore)! This was recovered from samples (along with gem-quality iolite) near the old strong mine along the 9th street road in the Laramie Mountains.

And what else did we find? At one location in extreme northwestern Colorado, 4 diamonds, 17 rubies and 24 pyrope garnets were panned. Wow, what a find! Actually, this was the site of the historical 1872 diamond hoax fraud which occurred near what is now called Diamond Peak. This diamond scam was amazing as it was an outcrop that was salted in 1871 and 1872 and the crooks scammed US Senators (first time in history that scam artists scammed scam artists). 

A primitive roller mill displayed at the Douglas Museum, Jerome, Arizona.
Eric Hausel stands adjacent to the mill.

References Cited

Hausel, W.D., 1991, Economic geology of the South Pass granite-greenstone belt, Wind River Mountains, western Wyoming: Geological Survey of Wyoming Report of Investigations 44, 129 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., and Stahl, S., 1995, The great diamond hoax of 1872: Wyoming Geological Association Resources of Southwestern Wyoming Guidebook, p. 13-27.

Hausel, W.D., Marlatt, G.G., Nielsen, E.L., and Gregory, R.W., 1994, Study of metals and precious stones in southern Wyoming: Geological Survey of Wyoming Open File Report 94-2, 61 p.

Exodus 25-11

Gold from Douglas Creek Wyoming. Photo shows gold recovered with the black sands removed (the penny is just used for scale). To remove black sands, simply wait until your panned concentrates are dry. Get a large and strong magnet, cover it with a paper towel and slowly sweep over the concentrates - whamo - nearly all of the black sands will be removed. What you have left is a little gold, garnets, mica and if you look close, you may even find diamond indicator minerals such as pyrope garnet, chromian diopside, picroilmenite, chromite and/or diamond. Diamond has a specific gravity of 3.5 and will often end up in the black sand concentrates. Much of the lighter colored material will be removed during panning: most of which will be quartz with a little feldspar. Quartz has a specific gravity of only 2.7.

Mining on Douglas Creek using a long tom and a
dredge on a rotating platform with shovel.

Preparation For Gold Prospecting Trips

Claim post on Federal Minerals. I get questions about claim
staking, but I'm as confused as you are. Please contact the
US Bureau of Land Management for information and hope they
provide you with the correct information - they often don't.

As a prospector, you need to learn about maps. Topographical maps provide information on geography and show locations of hills, valleys, mountains, roads, trails, creeks and towns. Geological maps show rock outcrops in relationship to the geography and likely will have locations of mines, prospect pits, trenches, tunnels, veins, faults, shear zones and folds. Geological maps also provide information on types of rocks. 



Know what areas are open to mining claims. Much Federal land is open to claiming, but some is closed to claims. To find out what is open, visit you local BLM (no, not those idiots, the other ones) office. State land cannot be claimed but often can be leased. Private land cannot be claimed unless it has Federal Minerals under the private surface. One problem with mining claims is that new claims are constantly filed, and at the end of the fiscal year, others are not renewed thus claim maps change. Unfortunately, the BLM apparently decided to eliminate claim information on their website.  



Gold nugget found in Rock Creek, South Pass.

The BLM attempts to keep information up to date on this site, but like anything the government does, it is not always correct. So use it as a general guide for mining claims and claim activity then you need to follow up with research in the county courthouse. When prospecting in the field, watch for claim posts as these provide information on claim locations, although just because there are claim posts in the field, this does not mean that the claim is active or even legal. 

Other sources that are excellent for prospecting include Google Earth. With the aerial photos and associated maps on these programs, relationships between geology, topography, mines, prospects, roads and drainages can be seen from the air prior to visiting a area of interest. 

LEWISTON GOLD DISTRICT. Schedule a trip to the Hidden Hand gold mine and vicinity in the Lewiston district of the South Pass greenstone belt in Wyoming. The legal description for the Hidden Hand mine is SE section 5, T28N, R98W and map coordinates are 42o25’30’N; 108o32’39”W. Thus, if you examine the Radium Springs quadrangle and find section 5 with the Hidden Hand mine labeled on the map, it is in the southeast quarter of that section. Or by using the map coordinates, you should be able to zero right in on the mine with Google Earth.

Inside the power house at the Vulture Gold Mine ghost town, Arizona.

Topographical maps cover the area include 2 degree sheets (scale 1:100,000) and 7.5 minute sheets. The 2 degree sheets are especially useful. These can be neatly folded and carried in a shirt pocket, glove compartment, or day pack. They represent general maps covering broad regions that are great for planning field excursions and contain information on roads and geography. For greater details, 7.5 minute quadrangles (scale 1:24,000) are invaluable. Topographical maps are available at some sporting goods stores, outfitter stores, the WGS, US Geological Survey (USGS), University of Wyoming Geology Library and local colleges and libraries. The WGS and USGS will also have geological reports and geological maps, many which can be ordered on-line or over the phone.

 The coordinates of the Hidden Hand mine places it within the Radium Springs quadrangle near the top of the map. The map to the north is the Atlantic City map which may also be useful. Geological maps provide important geological relationships associated with the mine, such as rock types, nearby structures such as faults, shear zones, folds. Find a copy of the geological map of the Radium Springs quadrangle (Hausel, 1988e). Other geological maps in this area that will be of use Atlantic City (Hausel, 1989), Miners Delight (Hausel, 1992e) and South Pass City (Hausel, 2007). Now find a copy of Report of Investigations 44 (Hausel, 1991a). This report will be useful as it is a detailed discussion of the geology and gold at South Pass. Another report that will be useful when learning geology and rock types of the area is Reprint 49 (Hausel and Love, 1992). This report was put together for the Wyoming Geological Association and describes important rock outcrops and will lead you on a personal field trip through South Pass. Now, see if you can find Wyoming Geological Survey Bulletins 68, 70, 71, and 72.



A 7.5 ounce nugget found in tributary of Rock Creek, WY

The Hidden Hand mine is located about 8 miles east, southeast of Atlantic City along the Lewiston road (also referred to as the Oregon trail road) south of both the Lewiston ghost town site and Strawberry Creek. The mine is on a patented claim. Patented claims are claims filed under the 1872 mining law that had enough value the government allowed the claimants to purchase the property at a fair market price. This was done in the 19th century to try to stimulate interest in mining and development of the West (something the government today no longer does - now they just discourage development and protect bugs, flowers and dirt). Today, it is impossible to patent claims. Although I never had access problems to this mine because it sits in the middle of BLM ground surrounded by vast, empty, wasteland, it could easily be blocked off. There is a very disturbing trend that non-mining people buy patented mining claims and then close it off because they feel they have something of value when they have little to nothing other than coyote pasture. This is what has happened to many of the diamond deposits in the State Line and Iron Mountain districts. If it isn't the democrats stealing our future, it's the government stealing our land. Have you seen what the legislature did to the Carissa mine? This once potentially productive gold mine (it likely has more than a million ounces of gold in the ground) is now Wyoming's version of Disneyland.

When this district was mapped (Hausel, 1986c) I stayed in a tent near Lewiston for much of one summer and did not see another person all summer. But that was 25 years ago. Maps that cover this area include the Radium Springs 7.5 minute (1:24,000 scale) topographic and geological maps. 

Now if you examine Google Earth, you should see distinct foliation (closely spaced lines) in the Miners Delight Formation metagreywacke that trend to the northeast. The rocks in this area are folded, faulted and turned on end. Also noticeable is the alignment of the Burr Mine with the Hidden Hand mine and this trend parallels regional foliation. A nearly east-west to northeasterly trending line of vegetation is visible southwest of the Hidden Hand that represents a cross-cutting shear zone that intersects the primary shear at the Hidden Hand. There are several prospect pits and a number of backhoe trench scars (some remain open, others are reclaimed) cut perpendicular to the primary shear zone.

A portion of the Radium Springs Geological Map near the Hidden Hand mine by the author showing shear zones and mines in this part of the South Pass greenstone belt. Greenstone belts are famous for gold in veins and shear zones.

A few things to note on the map: (1) the mine is located at the intersection of a group of shear zones (wiggly lines). At least 5 shear zones (faults) are apparent in the field and on aerial photos. Because of this, the mine shaft sits in highly brecciated and incompetent rock. (2) The mines (black and white squares) and prospect pits (x’s) line up on the map and on aerial photos as these essentially follow the shear structures that are buried under a few inches of dirt. (3) The Hidden Hand shear zones are offset along faults (dark, solid bold lines) to the south (where they appear to terminate) and to the north at Strawberry Creek. (4) A few hundred feet of the shear structures continue under much younger rock and dirt labeled as Tu along the bank of Strawberry Creek. Thus there is likely some gold sitting under Tu. (5) Strawberry Creek and Burr Gulch likely accepted much of the eroded gold eroded during the past, thus downstream from these shear zones (to the east) would be a very good place to prospect for placer gold.

 

The shaft was sunk on a 10- to 30-foot-wide, N40oE-trending, 62oNW-dipping shear in chloritized, hematitic metagreywacke (the normally black rocks actually have a slight reddish to greenish hue due to rock alteration) The shaft was 110-feet deep and the shear was explored by at least 640 feet of drifts prior to 1926. Ore from the 30-foot level was reported to run as high as 75 opt Au (ounces per ton in gold). In 1916, about 1000 tons of ore with an average grade of 4 opt Au were reportedly stockpiled. Some specimen-grade material assayed 3,100 opt Au (since there are only 32,000 ounces in a ton, this indicates that this specimen contained 9.6% gold). I must point out that such high assays must be questioned and are suspect.

Samples of altered metagreywacke that I collected from the dump contained only trace gold (Hausel, 1989). This discrepancy suggests one of a two possibilities: (1) the reported assays were exaggerated or (2) that the property developed a reputation for producing excellent gold specimens that the mine dump was thoroughly picked over by collectors over the years. Little information about this district and mine has been published and the mine workings are inaccessible, thus it is difficult to provide much in the way of conclusions. In addition, the explored structure at the Hidden Hand mine exhibits considerable brittle deformation – something that is more typical of Laramide faulting (post gold mineralization) in this region.

When looking at the Hidden Hand or other prospects, mines and districts, try to learn as much as possible. Soon you will become an expert prospector. If a prospect has a vein, try following the vein on the surface: look for minerals that are described in the area. Try to visualize the vein in three-dimensions. What does the vein look like at depth, how far does it go into the earth: five feet, 500 feet or 5,000 feet? Does it pinch and swell at depth? Does it pinch to 1 inch, is it faulted at depth, does it swell to a giant vein? Of course you can’t be certain, but sometimes there are things around you that give you clues as to what might happen at depth. One minable gold vein in Yellowknife, Canada that I looked at several years ago was only 1 foot wide on the surface, but at 100 feet deep, it is 8 feet wide and rich in gold! What angle does the vein project downward into the earth? 

Outcrop of the distinctly dipping Vulture vein.

Now it’s time to call on the wisdom of Albert Einstein because we need to take a trip back into geological time. If we could step into a time machine and go back about 50 million years, what would the vein and surrounding topography look like? How far in the air would the vein (and surrounding country rock) have projected before erosion leveled the terrain to its current level: 20 feet, 200 feet or 2000 feet? Where did all of the gold in the eroded quartz vein go? If the level of erosion was 2000 feet, there could be considerable gold in the nearby creeks, gulches and draws. Is the vein folded? Folds in quartz are often great places to look for gold enrichment known as ore shoots. 

Limonite-stained gossan found in glory hole near the Vulture vein 
in Arizona.

As an example, look some photos of the Vulture gold mine in Arizona. The vein provides an excellent example of a dipping vein. The photo was taken along its strike (or trend) such that from the point the picture was taken, the vein continues perpendicular to the surface of the photo. Off in the distance is a wooden structure which represents part of the old headframe where a decline shaft was sunk along the vein. The dip of the vein or angle that it projects from the surface into the ground follows the flat surface along the left edge of the vein: here it dips about 40 degrees. But not only is the vein of possible interest. When you walk around this mine area, several things of interest pop up. To the right of the photo is a glory hole of altered rock that is gossaniferous and stained by tawny yellow to brown limonite that likely has some gold. This sits below the quartz vein. Sitting adjacent to this pit and on top of the rock unit is some eluvial and alluvial material that past gold miners thought might be of interest as they dug an adit into the material. In Arizona, there are lots of eluvial gold deposits that eroded from adjacent gold deposits (many are hidden today).  Also, by walking around the area, other things of interest include rehealed breccias (the angular rock fragments have been cemented together with silica rich material). These probably contain gold and in some of the rich porphyry copper districts in Arizona, similar breccia pipes are good indicators of mineralization at depth. And the possibility of older rocks in the Vulture area containing structurally controlled gold may be worth checking because the old vulture mill sits on old, folded schist and gneiss.