Monday, December 23, 2013

Prospecting for Gemstones

The author searching for gold in the Silver Crown district in Wyoming
in 2012. And I found some! Believe it or not, this one deposit has $3.5
billion in gold
(with some copper and minor silver) all siting within 
view of the State Capital Building in Cheyenne, and lying next to I-80
and a State Highway! It doesn't get more convenient than that!
As a gold or gemstone hunter or prospector, you should understand geology and geochemistry of rocks while keeping an eye open for a variety of gemstones, precious metals, base metals and diamonds. The more you learn, the better prospector you will become. Sorry, there is no way around it; it takes years to understand rocks and their chemistry, so I provide prospectors and rock hounds with information they can understand and use in the search for minerals and rocks in my blogs, blogspotsbooks and other publications. So, how come I don't charge you for these services? It's because I do not have any DNA characteristics of wealthy hoarders in this world, and will never be wealthy even though I've discovered $billions in gold, gemstones and other minerals. This is because I'm much more satisfied with science, Biblical archaeology, and seeing happy, positive people helping one another. Personally, if I hoarded $billions in an effort to scam the world and search for devious ways to poison others, I would be concerned about my next home in the afterlife

Heck, even I have a hard time understanding many geology professors when they add unnecessary jargon to confuse issues. Before they give any one a PhD, they should ask the candidate to provide examples of communication skills with the general public. They should also require them to prove they can teach, before they are allowed to teach others.

All of those valuable gemstones and gold found in rocks are related to chemistry of the rocks, invading fluids, and geological history. For example, if you look for gemstones with considerable aluminum - such as ruby and sapphire - look for host rocks that have lots of aluminum (mica-rich schists, etc) to contribute; or evidence that aluminum-rich fluids migrated through fractures. Then look at the past geological history - how deep were the rocks buried in the past (if at all), when did they uplift, how much erosion occurred, etc. I know this type of information is difficult to come across, but any clues will help. 

Years ago, I worked for the Wyoming Geological Survey at the University of Wyoming in Laramie. While working on a research project with the Department of Engineering in 1980, I began to search for disseminated gold and base metal deposits for the department. The University of Wyoming engineers were interested in conducting metallurgical and chemical studies for metal extraction in disseminated deposits. So, I examined the areas in Wyoming that potentially could have these types of deposits based on geology. I knew I needed some good source rocks for the gold and also some  volcanic rocks that were very hot in the geological past and this took me to only a couple of places - Mineral Hill in the Black Hills, Bear Lodge Mountains in the Black Hills, the Silver Crown district in the Laramie Mountains, the Rattlesnake Hills in the Granite Mountains, the Absaroka Mountains bordering the eastern flank of Yellowstone, and Yellowstone. Unfortunately, Yellowstone and the Absaroka Mountains were off limits since the Feds had withdrawn them from mineral exploration even though some of the rocks in this area are likely rich in gold. Oh well.

Two places I thought had very good potential for this project included the Rattlesnake Hills in central Wyoming, and the other was the Copper King mine in the Silver Crown district where a sizable gold-copper resource occurs in a deeply-erodedporphyry copper deposit that had been uplifted and exposed at the surface just a few miles outside the town of Cheyenne.

The GemHunter (that's me) spent more than 30 years searching the hillsides for gemstones
and gold in Wyoming for the Wyoming Geological Survey as well as for mining companies
in and outside of Wyoming. Now you can have your own consultant - in a book!
This 369-page book tells you where and how to find gemstones in Wyoming and in nearby
areas. In many cases you are provided with GPS coordinates to find these sites on Google
Earth. When you are ready to take a weekend field trip, all you have to do is convert the
GPS coordinates to your hand held GPS unit
and it could lead you to hundreds of gemstone
and gold occurrences.

Already, many people have report finding gold, labradorite, jasper, agate, opal, rubies,
sapphires, iolite and diamonds by using this book
.

One prospector even panned out many diamonds including one of the largest found in Colorado
 - weighing 5 carats! So, why wait for everyone else to find treasure that could be yours. To convert your Google Earth GPS coordinates to your hand held, just click on the GPS conversion box
at the top of the Gold Prospecting blogspot.

While consulting for Saratoga Gold and Strathmore Resources as an independent consultant looking for additional gold resources at their 2 million ounce gold-equivalent gold-copper deposit known as the Copper King in the Silver Crown district near Hecla, Wyoming. And I believe I found a continuation of their gold deposit by 'reading' the rocks: it was down-dropped along a fault in the geological past and now lies under shallow, alluvium-covered basin to the east of the primary deposit. So, within reach of Cheyenne, there is a minimum $3.6 billion (at $1,800/ounce gold price) gold-copper deposit with much of it sitting at the surface and an untold amount of gold remaining to be drilled. 

AND, for those of you who like to pan, you just learned you first, very important, geology lesson! Remember I mentioned the gold-copper porphyry was "deeply-eroded". Well, all of that gold in that deposit was emplaced during the Proterozoic! This is just a fancy way for geologists to say it formed sometime between 541 million years ago to as much as 2.5 billion years ago (actually, it is age-dated at around 1.4 billion years old). So, it has had a lot of time to erode, and all that gold has a very high specific gravity, so it will work its way to the bottom of those creeks that have been eroding the gold-copper porphyry! And some more geological jargon that is important: "uplifted and exposed at the surface". What this means is that it was actually uplifted as part of the Laramie Mountains during what geologists call the Laramide Orogeny, which simply means the mountains started to uplift along faults as much as 70 to 80 million years ago, allowing all of those rocks in those mountains to be exposed to erosion. So, for the past 80 million years ago, the rocks at the Copper King have been eroding! And guess what, all of the fine-grain gold has also been eroding. So, all you need to do (and as far as I'm aware, nobody had ever panned the streams in that area) is find a place where you can dig some stream gravel downstream, and walla - according to science, "there be gold"! And you might even find a diamond or two.

So, any streams draining this deposit will likely have some gold. The closer to the deposit, the better (not so with diamonds, they are so hard and have moderate specific gravity, thus they could easily be in streams in Nebraska, Kansas and Colorado, as well as Wyoming). So, check topographical maps, check Google Earth (41°8'42"N; 105°11'11"W) and start looking for places to find placer gold and diamonds! But please don't trespass on private property, especially mine.

It is interesting that the Copper King is deeply eroded based on its geological history - and so are the kimberlite pipes in the Colorado-Wyoming State Line district to the west along Highway 287 as well as the cryptovolcanic structures that lie in between. So, you might take a gold pan, find some public access, and then pan for gold and diamonds. Both will likely be found in a drainage or two in the area. And yes - I know most are dry drainages, so you may have to transport some dirt to water, or vise versa, or learn how to dry pan. When I taught prospecting short courses through the School of Extended Studies at the University of Wyoming, I periodically taught this technique. It works great in Wyoming because of all of the wind, but it also leaves you very dirty. So why hasn't anyone done this before? Good Question.

Not far from from the Copper King, I identified more than 50 cryptovolcanic structures that likely include one or more kimberlite pipes for an Australian diamond company (DiamonEx). Many kimberlites are known as sources of gem and industrial deposits. To see some of these structures, just use Google Earth and do a search for Twin Mountains Lakes, Laramie County, Wyoming and you will see an area on the areal photography that shows a major regional fold in the old Precambrian rocks with several, distinctly rounded to elongated lakes. Google Earth also provides different ages of photography, so take a look at the 1999 and 2002 vintage photos and you will see the lakes have what appears to be a white salt in the soil. If this is carbonate - it may have been derived from kimberlite as the old, folded Precambrian rocks are a poor source for calcium carbonate. You can test soils like these with 10% hydrochloric acid and the acid will free carbon dioxide and the soil will fizz like soda pop! But beware, our incredibly ethically-challenged government expects to outlaw carbon dioxide. Seems that politicians are looking to fill their pockets with our money based on numerous scams.

So, how dangerous is this carbon dioxide - you tell me the next time you drink a soda, exhale, or walk outside among the trees and grass. How is it that we keep electing dumber and corrupter politicians? Ha! Its because the only people who run for office are sociopaths and pathological liars. Back to the rocks. I found similar depressions (structurally controlled all over this region in Colorado and Wyoming - actually more than 300!

Large microcline feldspar crystal from Copper Mountain in
the Owl Creek Mountains of Wyoming. Although this crystal is
white, many of the feldspar crystals in State Line pegmatites
are pink to brown orthoclase feldspar.
Just west of these crypto volcanic structures, I found a few diamond deposits from 1977 through 1980, in the State Line district where several other diamond deposits had already been found associated with a rare rock known as kimberlite. Most of these were found by David Eggler, Mac McCallum and Chuck Mabarak.

So, what is a crypto volcanic structure? It is a structurally controlled depression that looks similar to an impact feature. And, who knows, some could be impact features. Years ago, I looked at one such anomaly in Kansas known as the Winkler Crater. This feature (39°29'25"N; 96°49'13"W) was initially identified as an impact crater until Doug Brookins spent some time on the ground and discovered the crater was filled with kimberlite instead - so it was a kimberlite pipe (volcano). Years later, Cominco American Mining Company tested the pipe and reported finding one micro-diamond in the kimberlite. And you can still see this anomaly on Google Earth. It is perfectly round, has a deeper green color due to the vegetation growing over the kimberlite, and you can still see the scars of the trenches dug in the kimberlite by Cominco American many years ago.

Smaller microcline feldspar crystal from Copper Mountain.
For those who might be interested; there are some pegmatites in the area between the Copper King and Highway 287. Pegmatites are dike-like, very-coarse-grained granitic rocks. And most found in this region have considerable milky-white quartz that prospectors call 'bull quartz'. Bull quartz is simply a massive, milky-white, unmineralized (no gold) chunk of quartz. Anyway, some pegmatites are visible along Highway 287 south of Laramie (41°1'57.73"N; 105°26'3.95"W) and a few were mined during world war II for coarse-grained feldspar. I was told the feldspar was used in the manufacture false teeth. Look for some of the old mine on Google Earth, you can spot these by their white quartz! So, look for the white quartz, and also look for any piles of blue ground in the region that might be kimberlite.

Anyway, in some of these pegmatites, you will also find some coarse-grained mica books, rare yellow-green, translucent to frosted beryl, and an occasional garnet - I found one crystalline garnet in the pegmatite off of Highway 287 that was 6 inches across - but the color and transparency were ugly! But the quartz is interesting. Periodically, one can find small, transparent, hexagonal quartz prisms in rock fractures, but most of the quartz is the bull quartz. The bull quartz in these pegmatites express piezoelectric characteristics very well.

Of course, someone will think you are totally crazy for doing this - but what the heck. Most of us rock hounds are a bit nuts. Take a large piece of the bull quartz in a dark closet (large so you don't miss and smash your toes) and hit it with a hammer. You will be able to see a very nice spark generated within the quartz. Pretty neat! But again, whoever gets curious and opens your closet door is probably going to call for a straight jacket.

Hope this blogspot helps you find a treasure - and in the following pages, I tell you about jasper, agate, and quartz. So, go fill up your back packs and let me know when you find a diamond or two or a few nuggets, but respect the private land owners - The GemHunter