Category Archives: diamonds

Diamonds are a Geologist’s Best Friend

There is evidence supported by geology that the Wyoming province could host a major diamond province. The Wyoming Craton is geologically similar to the Canadian Shield (North American Craton) where many rich diamond deposits sat in the back yard of Canadians until two individuals began to diligently search for diamonds in 1985. This led to the discovery of the rich Ekati diamond deposits and Canada’s first diamond mine in 1998. The discovery was followed by several other discoveries. If it wasn’t for those two prospectors – Chuck Fipke and Steward Blussom, geologists around the world would still be wondering where all those diamonds accidentally found in glacial till over the past century came from. So, why didn’t anyone search?

Diamonds were found in a group of kimberlites along the edge of the Wyoming Craton in 1975 in both Colorado and Wyoming. Several detrital diamonds were found in the Wyoming Province in Montana in the past and more recently diamonds were recovered in a kimberlite in that region. Additionally, kimberlites, lamproites and lamprophyres were found all over the Wyoming Province but these remain a scientific curiosity. Over the next three decades, Wyoming spent essentially nothing compared to the $billions that have been spent in Canada exploring and developing diamond deposits. Yet, hundreds of cryptovolcanic structures of unknown origin remained unexplored and have yet to be drilled in the Wyoming Province. Is the Wyoming Province also a major diamond province? After many years of talking to hundreds of geologists and prospectors about the kimberlites and potential placer diamond deposits, one prospector finally panned one of the many locations suggested by the author and reportedly found a cache of diamonds including one, flawless, 6-carat diamond   verified by a university in North Carolina.

New book on gemstones, diamonds, and gold tells
prospectors where to find these gemstones and how
to identify them. Rated 5 stars by Amazon customers
Cryptovolcanic structure near Douglas Creek in the Medicine Bow Mountains
of Wyoming. This has been suggested to be an impact structure, but it
is more likely to be a kimberlite pipe.
Thank you Gem World for recognizing
our website as one of the top 40
in the world
Another cryptovolcanic structure of unknown origin – kimberlite?
Two excellent quality diamonds found by prospector Paul Boden in 1977.
These were recovered with gold in a long tom build on Cortez Creek in the
Medicine Bow Mountains not far from the above cryptovolcanic structures

 

General map showing diamond mines and diamond anomalies in North America. It should be apparent there is
considerable potential. Much of the high potential for commercial diamond deposits are areas known as cratons (from
Hausel, 2007, 2008).
View of the Wyoming craton showing locations of kimberlites
and related anomalies.
The State Line diamond district. More than 130,000 diamonds were found in this area in or adjacent to kimberlites. The
diamonds ranged from microdiamonds to a 28.3 carat diamond. One diamond fragment from Kelsey Lake was thought
to have broken from an 80 to 90 carat diamond. Placer diamonds were recovered from Fish Creek along the northern
edge of Kelsey Lake (included one diamond that weighed 6.2 carats) and other placer diamonds were found in
Rabbit Creek next to the Sloan 1 and 2 kimberlites, and many placer diamonds were recovered from George Creek. It is
likely that hundreds of thousands of diamonds occur in the nearby streams.
Cryptovolcanic structure in Colorado. Even though there is some snow in the
shade, the white material forming a bull’s eye around the depression is all
calcium carbonate. The depression and surrounding hills are all formed of
granite with no known carbonate.
Another cryptovolcanic structure (circular depression) filled with water and surrounded by calcium-carbonate rich soil.
The depression sits on granite in Colorado. So, is this a kimberlite, an impact depression, or just a lake?

 

HOW & WHERE TO FIND GEMSTONES & GOLD

In the late fall of 2014, the author published a new book published by CreateSpace an Amazon company, describes dozens of colored gemstone, diamond, gold and other minerals and rocks. The book lets the reader in on secrets used to find raw gemstones, diamonds and goldin field.

One of several hundred cryptovolcanic structures
identified in the Colorado, Kansas, Wyoming region.
This anomaly turned out to be a kimberlite pipe and
was discovered nearly 25 years ago in Colorado by
diamond mining companies.

 

 

Written for geologists, prospectors and rock hounds with some background in mineral and rock identification, the author not only provides information on the physical appearance of raw gemstones, but also describes many diamond, gold, ruby, sapphire, iolite, beryl, and other gemstone deposits giving locations using GPS coordinates and legal descriptions so that the reader can visit the deposits on Google Earth and on topographical maps. The author takes another step in describing areas likely to have undiscovered gemstones based on favorable geology – in other words, a few readers likely will find new gemstone deposits based on the information (some people already have)!
There are many cryptovolcanic structures visible on Google Earth that appear to be similar to kimberlite pipes. This is significant in that kimberlite pipes are known as potential hosts for diamond, garnet, chromian diopside and other gemstones. Nearly all of the cryptovolcanic structures identified by the author, remain unexplored in the field.

In another example, the author describes dozens of silicified fractures in an region covering several square miles that likely have quartz, chalcendony, agate, jasper and even opal. These too remain mostly unexplored.

Kimberlite and Lamproite – Host Rocks for Diamond

Chuck Norris’s cousin, Vic, digs for hidden kimberlite under grassy vegetation
anomaly discovered by the Gem Hunter in the Iron Mountain kimberlite
district in Wyoming.

Kimberlite is very difficult to recognize. It is basically a potassic peridotite and comes in a variety of colors and textures. Most notable is green kimberlite due to abundant serpentinized olivine.

It typically erupts from a feeder dike complex at depth and rises to a pipe-like structure known as a diatreme and blows out at the surface like a canon under great pressure.

Hypabyssal facies kimberlites samples fro the Iron Mountain district, Wyoming. Note the large, rounded mineral grains –
 these are hematite -serpentine pseudomorphs after olivine. This type of kimberlite forms in dikes and at the ‘blow’ of the
 the kimberlite pipe.
Hypabyssal facies kimberlite, Masontown, Pennsylvania. This kimberlite dike is enclosed by black shale.
Almost looks like basalt, but this is a sample of Ison Creek kimberlite I collected in 
Kentucky, known as basaltic kimberlite.
Snap Lake hypabyssal facies kimberlite, Fort Smith, Canada.
Diamond-bearing diatreme facies kimberlite breccia from Lake Ellen, UP, Michigan.
You probably would never have guessed this to be kimberlite. This bleached, tuffaceous, crater facies kimberlite from the
 Iron Mountain district, Wyoming has some pyrope garnet and picroilmenite and looks more like scoria than kimberlite
IG3 Kimberlite from Iron Mountain. Another tuffaceous kimberlite.
The Ferris 2 kimberlite from Wyoming.
Large fractured chromian diopside (chrome diopside gemstone) megacryst in Sloan 2 kimberlite from Colorado.
Gemstones like this are typically not recovered from diamond mines even though they are as beautiful as any emerald.
Kimberlite from the Victor pipe in Canada.
KelseyLake-14.2-cts-Copy

How to Identify Diamonds in Nature

14.2 carat octahedral diamond from
Kelsey Lake, Colorado (photo
courtesy of Howard Coopersmith).
In addition to the type of diamond we see at weddings, other varieties of extremely hard natural carbon are known including carbonado (polycrystalline) and lonsdaleite (hexagonal). These are all forms of carbon, as is graphite. But carbonado and lonsdaleite are very rare compared to natural diamond (which in itself is very rare). For information on lonsdaleite and other natural forms of hard carbon, refer to Erlich and Hausel (2002). Only crystalline, isometric diamond (the kind of diamonds we buy from jewelry stores) will be considered. For information on other natural diamonds, check out my books at Amazon.
In its simplest form, isometric diamond is an equal-dimensional mineral that may form six-sided crystals known to mineralogists as hexahedrons; but to prospectors, these are simply cubes. A more common habit (form) of diamond is the octahedron. To imagine what an octahedron looks like, try to visualize an Egyptian pyramid. Now imagine that pyramid surrounded by a crystal clear lake with its refection in the water. It would appear as if two pyramids were attached at the base: this would be an eight-sided octahedron.

Modified octahedron with many more faces.
Many octahedral crystals develop ridges on the octahedral faces resulting in crystals of trisoctahedral or hexoctahedral habit. Partial resorption of octahedral diamonds produce rounded dodecahedrons (12-sided crystals) with rhombic faces. Many dodecahedrons have ridges on the rhombic faces resulting in a 24-sided crystal known as a trishexahedron. Four-sided tetrahedral diamonds are sometimes encountered that are thought to be distorted octahedrons. Another relatively common form of diamond is a macle, or twinned diamond. Diamond macles appear as flattened triangular crystals. It should be obvious that diamonds have many crystal habits, so if you would like to know more about these, it is recommended to read Bauer (1968a) and Bruton (1978).

Most diamond surfaces will have growth trigons (equilateral triangles) and less commonly trigonal pits. And some will have hexagons (6-sided pits or raised areas. You are likely getting the idea that there are many complexities to understanding diamond crystal habits or shapes. But don’t despair. If the above information snowed you, just remember there is a simple instrument known as a diamond detector sometimes called a diamond detective that you can purchase on-line for a minimal price. It will tell you if you have a diamond or not by simply touching the crystal and pressing a button. Nothing could be simpler for a prospector, rock hound and even geologist and gemologist.
Magnified diamond surface showing several trigons.
Diamonds have distinct, brilliant, greasy luster that is likened to oiled glass. Often quartz is mistaken for diamond, but the dull luster of quartz is no match for the brilliant adamantine luster of diamond. Gem-quality diamonds can be translucent to transparent, colorless, green, yellow, brown, black and rarely blue or pink. Opaque and heavily included diamonds (bort) are used for industrial purposes and have little value.
Diamond is brittle, extremely hard (H=10 on the Moh’s scale), with a specific gravity of 3.5, and has perfect octahedral cleavage. Even though diamond is heavier than water, it is non-wettable (hydrophobic) and will float on water given the right circumstances. Some flotation devises have been designed to extract diamond using water’s surface tension. Being hydrophobic, diamonds are also grease attractive. This property is used to recover diamonds in many places around the world, where shaking tables are coated with grease to extract diamonds from concentrates run over grease tables with water. The grease, usually a mixture of Vaseline and paraffin in a 10:1 ratio, is coated on the shaking table surface.

Under ultraviolet light, many diamonds fluoresce pale blue, green yellow, and rarely red. This characteristic of diamond is used in many diamond mills, such as Sortex, which detects fluorescence from diamonds when they are x-rayed.
Since diamonds are extremely rare, it takes considerable effort and patience to find the gemstone. It has been estimated diamond occurs in concentrations of less than 1 part per million in commercial diamondiferous kimberlites. This means you have 999,999 parts of waste rock to run through to find that 1 part per million diamond only after you have searched and searched for the primary host rock. And not all kimberlites, lamproites and lamprophyres have diamond.

Sloan kimberlite, Colorado. This kimberlite contains diamonds as well as
other gemstones including Cape Ruby (pyrope garnet) and chromian diopside.
Years ago, it was common knowledge in the mining industry that only about 10% of kimberlites contained diamond (Lampietti and Sutherland, 1978; Hausel, 1998). This estimate was not quite correct as many other rocks at the time had been erroneously classified as kimberlite – and over the years, there has been a lot more kimberlites found (Hausel, 2008a). So the percentage of diamondiferous verses barren kimberlites is much higher than originally thought. But at the same time, the percentage of diamondiferous verses barren lamproites and lamprophyres is very low.

Iron Mountain kimberlite, Wyoming
The primary rocks that diamond is found in are known as peridotite and eclogite. These are rare mantle-derived rocks (nodules) that are actually sampled, or picked up by rare volcanic eruptions (i.e., kimberlite, lamproite and some lamprophyre). Thus the kimberlite, lamproite and lamprophyre magmas accidentally pick up these rare diamond-rich rocks at great depth and bring them to the earth’s surface in rare old volcanoes. Many of the diamond-rich nodules survive intact after being shot out of the earth’s mantle from depths of 90 to 120 miles, while others break up with their diamonds being diluted in the magma. As an example of how rich some primary host rocks are, one sample of eclogite from the Sloan kimberlite in Colorado contained an estimated 20% diamond! But kimberlite magma itself, was many times poorer in diamond than this eclogite.
No other mineral (other than gold) seems to elude correct identification by prospectors and rock hounds. This is because of a poor understanding of mineralogy and because most people tend to see things that don’t exist and let their imaginations run wild. After 30 years of working with the public and identifying samples for people almost on a daily basis, I only had two people who correctly identified diamond. Many hundreds thought they had diamond, but were seeing things that were just not there.

I have many stories about these prospectors and rock hounds that are both educational and interesting. One prospector called me from his truck at Jeffrey City and wanted to know what to do with all of the diamonds he had found. I was impressed: “How many did you find?” I asked.
“There are thousands all over the hill side!” He responded.
Being curious, I asked him, “How are you verifying these diamonds?”
“I just scratch the windshield on my truck, and they leave a nice scratch”, he responded.
Being a wise ass, I asked, “Are you going to be able to see out your window well enough to drive home?”

He was right, diamonds will scratch windshields! Windshields are made of glass with a hardness of only 5.5 to 6 on the Moh’s scale. This means many minerals will scratch windshields including pyrite, feldspar, corundum and of course quartz. One way windshield’s become pitted (scratched) during dust storms is due to all of the fine sand that is blown into the windshield.

A fairly inexpensive design for a grease table constructed by Jay Roberts at
the Wyoming Geological Survey. The light-bluish white coating is the grease
mixture. The problem with this material (particularly on a university campus)
was that we had to buy Vaseline by the case. We often received accusing
expressions from drug store employees assuming we were with a fraternity
planning for some weekend orgy.

Another prospector called and said he had been diamond hunting for years and never found any. After talking awhile he mentioned his method for diamond testing: “I simply put them on an anvil and hit them with a hammer!” He talked about all of the octahedral crystals he had picked up from streams and kimberlites in the Colorado-Wyoming State Line district (where several known diamond deposits occurred) but none were diamonds because they all failed his test!

A giant diamond from Africa – 620 carats in weight. This diamond was actually on display for a short time at Wiseman’s
Jewelry in Laramie, where I was able to photograph the extraordinary stone.
I then explained to him about the difference between hardness and mechanical brittleness and that all diamonds will break when struck by a hammer. You could hear that sound of … well, it sounded like muffled swearing in the background as he hung up.
In another case, I received a phone call from an individual who claimed to have found the largest diamond in the world just west of Cheyenne. According to an unnamed gemologist from Cheyenne, this crystal was pronounced to be diamond. But the gemologist suggested that before the prospector put it on and purchased a large mansion on the French Riviera, he should visit my office in Laramie for a second opinion.
I gave him directions to my office. It’s about an hour’s drive from Cheyenne, so I was surprised when he and his three family members were knocking on my office door about 30 minutes later. They were apparently anxious to cash in their millions.
The diamond discoverer introduced himself as ‘Jack’ and did not give a last name, and without further hesitation, opened a locked brief case chained to his wrist and showed me the ‘Star of Cheyenne’. It was fist size – about the same size as the famous Cullinan diamond. The Cullinan was by far the largest diamond ever found and weighed a whopping 3,006 carats and was recovered at the Premier Mine in South Africa. It was priceless and ended up in the Crown Jewels of England.

Kimberlite? Nope, some prospectors would call this kimberlite, but it is
actually a lamproite.
In the late 1970s, I had met Dr. Arnold Waters. Dr. Waters was at the time, the former Chief Geologist for DeBeers in South Africa and he told me that when the Cullinan was found, it had a distinct cleaved surface where part of the diamond had been broken in two during assent to the earth’s surface in a kimberlite magma (volcano). He indicated the other half of the diamond could have been as large or larger, but was never found! Did it break off somewhere at great depth and still many miles deep in the earth? Did it make it to the surface and was missed by the sorters and ended up in the crusher where it made many little diamonds? It’s something to wonder about.

The ‘Star of Cheyenne’ was reluctantly handed to me. As soon as I saw it, I knew what it was, but decided to have a little fun. First I showed them how to test a mineral’s specific gravity by weighing the gem in water and then in air. I determined the crystal to have a specific gravity about 2.7 – too light for diamond (diamond’s specific gravity at 3.5 is heavy enough it would show up with garnets and black sands in a gold pan). I also tested the hardness by taking a diamond chip and easily scratching a deep notch in the crystal. This resulted in an immediate protest by the family as they thought I was scratching their priceless diamond.
“Hold on!,” I exclaimed. “If this were a diamond, I wouldn’t be able to scratch it with a diamond chip, diamond has a Moh’s hardness of 10 and is the hardest known natural mineral, and it is very, very difficult to scratch a diamond with another diamond”. After I calmed them down and convinced them that they had an ordinary piece of rock crystal (transparent massive quartz), they left the office dejected and drove back to Cheyenne with visions of mansions and Porches fading. And I thought this was over.
The next day, I was contacted by one of our other geologists – Ray Harris (RIP) – who stopped in my office to tell me he had just received a call from a person in Cheyenne who had a probable diamond that he wanted to have verified. The person on the phone explained to him that they had already talked to me, but he and his gemologist decided that another opinion was necessary.
The diamond detective – yep, that’s me when I was VP of US Exploration for DiamonEx Ltd, Australia. During exploration
 in Colorado, Montana, Kansas and Wyoming, we identified hundreds of cryptovolcanic structures that look almost like
 impact craters with the exception that these are structurally controlled – located on a fault or similar feature. Would you
 like more information from the Gem Hunter? Follow me on Facebook and link to my GemHunter website.
Ray went back to his office to await the family. I laughed to myself. Ray was a very good geologist, but he had a reputation as a klutz. He was famous for running into things, breaking things, and if anything could go wrong – leave it to Ray. One of my favorite stories about Ray took place at a staff meeting. Ray was holding a cup of coffee in his left hand. I notice this and decided to catch him off guard. So I quickly asked him for the time of day. Without hesitation, Ray rotated his wrist to look at his watch pouring his coffee into his lap. We all had a great time with Ray, but during his last year, he was bullied by his supervisor until he died. I will always miss Ray – he was a good friend.
Prismatic quartz crystal from
Hot Springs Arkansas

Anyway, the Cheyenne family arrived with their gem. They talked about the gemologist’s opinions and their concern about my scratching the diamond. I don’t know if Ray had ever seen a diamond in the rough before (few geologists had) and after examining the fist-size specimen with his hand lens, he decided to get a better look at the gemstone and carried it to his microscope in his adjacent lab with the family following him. Then it happened! He lost control of the sample and it crashed onto the floor shattering into dozens of pieces.

Blue quartz from Montana

Ray told me the family turned white as ghosts. But Ray consoled them looking down at all of the pieces. “Well, guess it wasn’t diamond – it has conchoidal fracture”. The family scooped up the fragments of their precious quartz and went home, never to be seen again. When Ray told me about his event – I laughed, and pointed out to him that diamond (as well as quartz) has conchoidal fracture. Ray turned white. But don’t worry – it was just a piece of quartz.

Sweetwater agates (quartz) from the Granite Mountains, Wyoming

Figure-1c

Kimberlite Pipes and Volcanoes

Would you like to see a kimberlite volcano erupt? Me too! Watch the following animation – but don’t stand too close. These kimberlite eruptions are very explosive and at the point of eruption, likely have a gaseous emplacement temperature at the freezing point of water and velocities of Mach 3!!!
Below are some photos of kimberlites, diamonds, books, etc.

High-wall with exposed diamond-bearing kimberlite breccia at the Kelsey Lake mine, Colorado. If you have Google Earth on your computer, search for ‘Kelsey Lake, Colorado’ to see the location of the blue ground to see this former diamond mine. Note the large angular rock fragments in the highwall – these indicate there was a tremendous amount of explosive energy during the eruption of this kimberlite pipe (photo by the author – Gem Hunter).
Diamond-bearing Schaffer kimberlite dike in Wyoming exposed in dozer trench in 1979 or 1980. Jay Roberts, geologist, stands in the trench for scale while I took this photo. The kimberlite is the gray-blue material. The reddish material in the foreground is sheared Proterozoic granite (Sherman granite facies).
Diamondiferous kimberlite from the Sloan 2 pipe in Colorado. Note the large, rounded pyrope garnet.  The Sloan kimberlites have identified diamond resources and remain mostly untouched. DiamonEx had acquired the Sloan property in 2007 under my direction, but the 2008 economic collapsed took its toll on world diamond prices, the company, and the world. The property was abandoned by DiamonEx, yet it likely still encloses hundreds of $millions in diamonds.
Kimberlite (Devonian) and Granite (1.4 billion years old) contact exposed 
by bull-dozer, Schaffer kimberlite complex, Wyoming. 
Note how sharp the kimberlite contact is and there is no
 evidence that the granite was baked.
Maxwell diamondiferous kimberlite in Colorado – one of many kimberlite pipes and dikes in Colorado and Wyoming that still remains untested for commercial diamonds. Diamonds were recovered from a small sample from this pipe (C.D. Mabarak, personal communication).
Buried kimberlite dike in Wyoming – the kimberlite underlies 
the dirt in the right half of the photo where there appears to be 
thicker and slightly higher vegetation.
Diamonds in the US?  From Diamonds and Mantle Source Rocks in the Wyoming Craton – by W. Dan Hausel, 1998. The diamond-shaped figures represent reported diamonds. The triangles are kimberlite localities (open triangles are diamond-bearing kimberlites), squares are high-pressure volcanics similar to kimberlite, + are lamprophyres and lamproites, the + enclosed by a diamond is diamond-bearing lamproite, the white diamond is the location of the Great 1872 Diamond Hoax site, the dots represent kimberlitic indicator mineral anomalies of note.
Some of the high-quality gem diamonds from Kelsey Lake mine (photo courtesy of Howard Coopersmith).
Close-up of diamond surface with some of the distinct trigons etched in the 
surface.  Don’t know how to identify diamonds? Its not all that difficult. If 
you do not have a background in mineralogy, all you need is the 
Diamond Detector – you can even make your own.
Popular book (129-pages) on diamonds in the US – you might be able to buy this at the Wyoming Geological 
Survey at the University of Wyoming- but I recommend downloading it for free from my website.
Book on rocks and minerals that also has brief information on diamonds and on kimberlite and 
lamproite. Available at  Amazon
Another popular book on gemstones (and diamonds) that the Wyoming Geological Survey forgot to reprint after the current edition was sold out. Photo by Wayne Sutherland.
Gem kyanite from central Laramie Mountains (we found billions of 
carats of this gem – but it remains undeveloped). 
Some of this gem is found with iolite, ruby and sapphir
in the central Laramie Mountains.
Booklets on diamonds from the wyoming geological survey (photo by Wayne Sutherland).
Free pamphlet on diamonds – this may still 
available in Wyoming.  If not, you can 
download a copy at the  GEM HUNTER website.
Rough diamond from Wyoming – wow, aren’t 
these stones beautiful! Note how the gem has kind of a 
greasy luster. This is characteristic of diamond.
Exploration methods for kimberlite – this was one of the first 
diamond publications I published. I was excited about t
he publication and the work I did. For me, this was the perfect 
job with imperfect wages. But what the heck, you can’t 
have everything.
Recent publication on geology of the Leucite Hills lamproites and possibilities of diamonds in the Leucite Hills lamproites in Wyoming (may or may not be available at the Wyoming Geological Survey).  I loved  working in this area. While conducting research on diamonds, we recovered diamond-stability chromites from some of the lamproites (this suggests the chromites formed under pressures and temperatures similar to that of diamond formation; thus there is a possibility for diamonds in this region).
Essentially all of the projects at the Wyoming Geological Survey were so underfunded, its amazing we found anything. Even though these rocks may contained diamonds, we were unable to test any material (other than a couple of rocks). Elsewhere in the world, there is a correlation between olivine and diamond content in some lamproites, so I was excited to find a couple of anthills with considerable olivine in the northeastern portion of the Leucite Hills. After looking at some olivine with a hand lens, it was apparent nearly all was gem-quality. So I took the two anthills in sample bags – and Robert Gregory processed the material (no diamonds were found), but we recovered 13,000-carats of gem-quality peridot from this sample!
Diamonds in the world – great book, but price is too high 
(don’t blame me, I received no royalties for this book 
and the publisher ignored all protests about the price – 374 pages.
Ruby from Granite Mountains, Wyoming. Specimen found by Eric Hausel.
Book  (42 pages) on a little known diamond-bearing kimberlite district in Wyoming. We didn’t find any diamonds (found lots and lots of diamondbacks) – nor did we test any material for diamonds. However the geochemistry of all of the rocks showed that they all originated from the diamond-stability field and a couple of diamonds were reportedly found in the early 1980s by Cominco American.

Kimberlite ‘diamond’ Indicator minerals. These include pyrope garnet, spessartine garnet, pyrope-almandine garnet, emerald-green chromian diopside, picroilmenite (black metallic with white leucoxene crust) and two tiny black, octahedral chromites. Here is an example of how geologists miss gemstones. These were all recovered from the Sloan 2 kimberlite in Colorado when I was working for DiamonEx Ltd. Everyone working in this region for years focused only on the diamonds; yet these are all gemstones and can be faceted into beautiful colored gems while the chromites and picroilmenites could be fashioned into low-value gem cabochons.
Guide to finding gemsgold, diamonds and rocks in Wyoming. If you can’t find it at the Wyoming Geological Survey, you can download a copy from the GemHunters website.

There are many gemstones in Wyoming. Most people would have laughed if you told them in 1975 that Wyoming had the greatest variety of gemstones in the US. In 1975, Wyoming had known jade deposits and some agates – but that was about all.

Over three decades, the more I looked, the more I found: dozens of overlooked gemstone deposits and evidence for hundreds more which included commercial gold deposits along with more than 100 gold anomalies.  It was my intention to continue this research along with educating the public to help YOU find gemstones, diamonds and gold using methods I found successful in finding a few hundred mineral deposits.

But morally and ethically, I could no longer work for the Geological Survey or the State of Wyoming, so I moved on. Since 2006, there have been no discoveries of new metal or gemstone deposits.

My latest book includes information on diamonds and
kimberlite. Find it at Amazon.
Follow us on Facebook and Gem Hunter and learn more about gemstones and gold.

Need More Information – Check out the Older Posts 

481B

Wyoming – The Gemstone State.

Gem-quality pyrope garnet faceted from rough collected at Butcherknife
Draw near Green River, Wyoming.
Colored gemstones were almost unheard of in Wyoming prior to 1977 other than some fabulous cobbles and boulders of jade, some petrified wood, a few agates and a couple of tiny diamonds that required a microscope to see. After I was hired as the Senior Economic Geologist at the Wyoming Geological Survey, I began first to search for diamond deposits, then gold, and along the way, I got interested in gemstones, their geological settings and necessary conditions for formation (chemistry, pressures and temperatures) (Hausel and Sutherland, 2006). It soon became clear that several variety of gemstones should be found in Wyoming but few were ever reported. 

So I went looking and was amazed at all of the gems, diamonds and gold that had been overlooked in the Cowboy State: I kid you not – some sitting right along the highway! And I can guarantee there is a lot more, but it seems like nothing is being done since I left Wyoming in 2007 even though I had found evidence for hundreds of more diamond deposits, gold deposits, a few palladium deposits, several ruby deposits, more iolite deposits and possibilities for emeralds and other beryl deposits (aquamarine and helidor) just to name a few.

A beautiful lady with transparent
jade in necklace.
Over the years, I mapped more than 1,000 km2 of complex Precambrian geology along with mapping some younger volcanic terrains: it became clear that Wyoming should have a wide variety of gemstones – but there were few reports of gems being found in the State and little evidence that anyone had been or was looking. After I formulated some ideas on what to look for I soon started making discovery after discovery. Along with my discoveries, some rock hounds were also making interesting discoveries. If only I could have been allowed to continue searching, I would have made many more discoveries.
I found dozens of gemstone deposits and possibly the largest colored gemstone deposit on earth. I recovered the largest iolite gemstones on earth (one weighing >24,000 carats) and left some in the outcrop that would dwarf these giant gemstones. A few I estimated would weight >100,000 to 1,000,000 carats and would require jackhammers and a dump truck to get them out! Yet these and other giant gemstones remain where they are all because of one corrupt state geologist and his governor buddy.

I also found evidence for additional ruby and sapphire deposits in the central Laramie Range, Granite Mountains, Owl Creek Mountains and southern Wind River Mountains after finding seven previously unknown ruby deposits. And I began chasing more opal deposits where ever the countryside had been blanketed by Tertiary to Recent ash falls from past eruptions from the Yellowstone caldera (I had already found one of the largest opals on earth that weighed more than 77,000 carats with larger stones left in the field and also found a large deposit of fire opal). I was searching for other gems including possibilities of emeralds in the Sierra Madre and Overthrust belt, investigating enormous amounts of sky blue kyanite, looking for more iolites, rubies, sapphires and aquamarines, and I had verified Colorado, Montana and Wyoming was underlain by a major diamond province.

Gem kyanite from Laramie
Range
It was clear, due to the unusual geology of Wyoming being a craton that was underlain by (1) very old Archean rocks (rocks greater than 2.5 billion years in age) that were subjected to very high pressures and temperatures resulting in their recrystallization and (2) some younger Proterozoic (2.5 billion to 600 million years in age) schists
and granites that had a wide variety of mineralogy and chemistry that were also subjected to high pressures and temperatures, (3) younger Phanerozoic (less than 600 million years old) sedimentary rocks, (4) Tertiary and Quaternary volcanic rocks and ash falls and (5) rare kimberlites, lamproites and lamprophyres (subjected to extreme pressures), that Wyoming had many potential favorable host rocks for a large variety of gemstones – but no one had bothered to look.
I began to search for different gemstones keeping in mind the geological environments and the rock chemistry. I started to make lists of what I might find and kept extensive files on various gemstones and their geological environments worldwide. While I was mapping, I was also searching for gold, base metals, strategic metals, gemstones and decorative rocks. Soon I was finding many gemstones on my list. Here is the list of what I started searching for and finding in many cases:

Giant jade boulder from Jeffrey City, Wyoming.
Agate, aquamarine, almandine, andalusite, andradite, amethyst, apatite, azurite, ammolite, apache tears, amber, ametrine, barite, bloodstone, blue chalcedony, bronzite, burgundy diamond, canary diamond, carnelian, chalcopyrite, champagne diamond, cherry opal, chocolate diamond, chromian diopside, chromian enstatite, chrysoberyl, chrysocola, chrysoprase, citrine, common opal, clinozoisite, cuprite, dendritic gold, nugget gold, platinum, palladium, drusy quartz, emerald, epidote, fire (mexican) opal, fluorite, fuchsite, garnet, gold, golden beryl, golden sapphire, goshenite, green aventurine, green tourmaline, heliodor, hiddenite, idocrase, iolite, jade, jade pseudomorphs, jasper, jasperoid, jasper breccia, kunzite, kyanite, labradorite, lemon serpentine, lepidolite, malachite, maxixe, black opal, moonstone, morganite, moss agate, onyx, oriental sapphire, peridot, pink diamond, pink sapphire, precious opal, prehnite, pyrite, pyrope, quartz, rock crystal, rose diamond, rose quartz, rubellite (pink tourmaline), ruby, rutilated quartz, rutile, schorl, specular hematite, scapolite, sillimanite, silver,  smoky quartz, sodalite, spessartine, sphene, sphalerite, spodumene, star sapphire, tanzanite, tourmaline, tigerseye, varisite, white sapphire, zoisite and zircon.
A 12-carat, nearly flawless, rough pink sapphire recovered from the Palmer
Canyon deposit by Vic Norris.
The more I searched, the more I found. I also spent time educating rock hounds, prospectors, companies, geologists and mineral collectors in Wyoming and nearby states by providing lectures, short courses and field trips on how, where and what to prospect for. I also wrote many articles and books on prospecting: it was working. Soon I was not the only person looking for gemstones and others began searching and finding gems in the Cowboy State. Over 3 decades, I found nearly 75% of the gemstones on my list and I suspect if I would have been able to continue my research, I would have found many more deposits and possibly as many as 85 to 90% of the gems.
Flawless pyrope garnet I collected at Butcherknife
Draw, Wyoming and sent to Sri Lanka for faceting.
I was in demand to give talks all over the country and many people were showing up to my lectures carrying all kinds of minerals and rocks previously unreported in Wyoming including things like gem-quality labradorite found in road bed material from Albany County 11 and 12 where I had recently found a breccia pipe with limestone xenoliths adjacent to a significant kimberlitic mineral indicator anomaly that we had identified prior to 1988. Others found diamonds in anthills in the Green River Basin and a few showed up with beautiful specimens of gold nuggets (one person had more than a hundred high-quality nuggets from South Pass and another showed me ball jars full of gold nuggets and dust from the same region), jasper and agate.
I had found many previously unreported kimberlites and kimberlitic indicator mineral anomalies in the Iron Mountain district near Chugwater and this attracted prospectors to dig for diamonds. I visited the Great Diamond Hoax site in northwestern Colorado where I recovered diamonds, rubies, and pyrope garnets salted by scam artists in 1872. But then I was told by Dr. Tom McCandless that Diamond Peak actually had conglomerate containing gem-quality pyrope garnet and chromian diopside (both diamond indicator minerals). What was the chance of this happening? 
Diamond companies started to show up in Colorado, Montana and Wyoming. And the Kelsey Lake diamond mine opened on the border south of Laramie – but soon closed due to legal problems. Other companies picked up other properties in the same area and found enough diamonds for commercial production. Between 2004 to 2006, the Wyoming Geological Survey was decimated by a sociopath who is still on the loose. For ethical and a reasons, I decided to take early retirement and run US exploration for DiamonEx Ltd, an Australian Mining Company with interests in Botswana. And I had a wonderful time until the market crash of 2008, which put several small mining companies out of business.
Gem kyanite cut into cabochons from Palmer Canyon, Wyoming.
There are literally hundreds of billions of carats of this gemstone
in eastern Wyoming at Palmer Canyon, Cooney Hills, Grizzly
Creek and likely in other areas of the state (Hausel, 2009). These and other
aluminum-rich minerals are often found in what geologists call metapelite
(mica-rich schists) that was subjected to moderately high pressures and
temperatures. Using this information, I found dozens of these deposits around
Wyoming. The colors and fractures in these gems actually enhance their
appearance. I am very surprised that someone has not tried to market these
as they are relatively easy to cut. They are a low value gem, but when there
are billions of carats – who cares.
While at the Wyoming Geological Survey on the University of Wyoming campus, I had received regional and national awards for communication skills including the American Association of Petroleum Geologists President’s Certificate and the Wyoming Geological Association’s Distinguish Service Award for my research on Wyoming’s geology and for the dozens of talks I had presented at that society. I had also been twice nominated for the Dibble Mapping Award by two former directors of the Wyoming Geological Survey – Gary Glass and Dr. D.L. Blackstone, Jr. The Laramie Lyceum had presented me Distinguished Speaker of 1994 and the University of Wyoming Department of Geology & Geophysics included me as Distinguished Lecturer and these were just some of the national and international recognition I had received over the years for being a great communicator. When I was in college at the University of Utah, I had been employed as an astronomy lecturer at the Hansen Planetarium because of communication skills. But what the heck, what did all of these people know including Who’s Who in America, Who’s Who in Science, Who’s Who in the World, 2000 Notable American Men, etc.
I was considered to be one of the few specialists in Archean gold deposits, diamond deposits, colored gemstone deposits, greenstone belts and more. I was told by the chairman of the Geology Department at UW, that it was only because of my work and research that geologists had a good grasp of the Precambrian Geology. I had been awarded and inducted into two different Halls-of-Fame (nominated for a third) for my geological research, education efforts and communication skills, something that I suspect no other geologist in Wyoming (and possibly the US) could claim.
Giant ruby found in the Granite Mountains. This was at one time the largest ruby ever
found on earth – but unfortunately, much of the ruby (purple red) was replaced by zoisite
and fuchsite (green matrix). However, it suggests that exploration of this deposit will
potentially result in discovery of some of the largest rubies on earth.
I had found one of the largest gold deposits in North America, found a whole new gold district with commercial gold mineralization, studied hydrothermal alteration characteristics associated with a large disseminated gold and copper deposit, identified more than a hundred gold anomalies, dozens of gemstone deposits, a couple of massive sulfide deposits, one of the few nickel anomalies ever to be found in Wyoming with some palladium and platinum and more (for which I gained nothing other than recognition and my personal education). I mapped nearly every mining district in Wyoming along with the two largest kimberlite fields in the US and the largest lamproite field in North America, and I was in demand as a consultant for mining companies when I took annual leave from the Survey.
It was time to move on, so I went to work as VP of US Exploration for DiamonEx Ltd, where I found some diamond bearing kimberlites, identified several hundred possible kimberlites for the company to explore and drill.  After DiamonEx, Ltd, I worked as a consultant for other mining companies including Black Range Resources, Giant King Gold, Strathmore Resources, Wyoming Gold, Saratoga Gold and others. Personally, I love geology and I love hunting for new mineral deposits.
Transparent blue barite from Shirley Basin, Wyoming.
Cape Emerald from State Line district, Wyoming
Banded Jasper from Tin Cup district, Wyoming
1.1 carat faceted ruby from Palmer
Canyon, Wyoming
Enormous ruby faceted from rough collected in the Laramie
Range, Wyoming
Cabochon of specularite with copper from Charter Oak mine,
Wyoming
Gem labradorite from Sybille Canyon,
Wyoming.

Malachite with specular hematite from the Hartville area, Wyoming

chloritegarnet-Copy

Geology of Gemstone Deposits

Large chlorite pseudomorph after garnet found in the Sierra Madre Mountains, Wyoming. The chlorite slowly replaced
the garnet and accepted the garnet’s crystal form. 
Much of Wyoming is underlain by Archean cratonic basement rocks and cratonized Proterozoic rocks that provide favorable geological environments for a variety of gemstones – notably diamond, iolite, ruby, sapphire, garnet, kyanite, andalusite, sillimanite, labradorite, jewelry grade gold, platinum and palladium nuggets, emerald, aquamarine, helidor, tourmaline, spinel, clinozoisite, zoisite, apatite, jasper, specularite, etc. Thick Phanerozoic sedimentary rock successions with lesser Tertiary volcanic rock cover large portions of the basement terrain. Some of these Phanerozoic rocks provide favorable hosts for other gemstones including opal, placer diamond, placer gold, placer platinum, placer ruby, jasper, agate, emerald, varisite, etc.
Using traditional exploration and prospecting methods, dozens of gem and precious metal deposits were discovered over the past 3 decades, including major discoveries and geological and mineralogical evidence for significant undiscovered deposits. Major swarms of mantle-derived kimberlite, lamproite and lamprophyre, many of which have proven to be diamondiferous, also host colored gemstones including pyrope garnet (Cape Ruby), spessartine garnet, almandine garnet, chromian diopside (Cape Emerald) and chromian enstatite. One lamproite also yielded peridot.
Favorable conditions for crystallization of metamorphogenic gemstones during regional amphibolite-grade metamorphism occurred during the Precambrian. In this terrain, metapelite in the central Laramie Range hosts kyanite, sillimanite and andalusite. These three minerals provide evidence of favorable pressures and temperatures needed for crystallization of aluminous gemstones including ruby, sapphire and kyanite. Cordierite (iolite) another aluminum-rich gemstone, formed during a later thermal event. This later event was responsible for deposition of world-class iolite (Water Sapphire) gemstone deposits.

While searching for gold, I came along
this giant jasper deposit.
Evidence for undiscovered gemstone deposits is predicted based on mineralogical anomalies detected during various research projects from 1977 until 2005. These include ruby, sapphire, gold and aquamarine found in stream sediment samples as well as favorable geological terrains that remain unexplored. Other anomalies include pyrope garnet (several with G10 geochemistry), picroilmenite, and some chromian diopside that provide evidence for hundreds of undiscovered diamond deposits. Elsewhere, detrital diamonds reported by various prospectors provide direct evidence for undiscovered diamond deposits. Other geological and mineralogical evidence suggest the presence of additional undiscovered opal, cordierite (iolite) and kyanite deposits. Wyoming could potentially become a major source for gemstones including diamond, gold, platinum, palladium, Cape ruby, Cape emerald, iolite and opal.


Giant chrome diopside gem in kimberlite from Colorado.
Kelseylkdiamonds-jpg

DIAMONDS, DIAMONDS & MORE DIAMONDS

I love searching for diamonds. My first chance to explore for diamonds deposits occurred in 1977 when I was hired by Dr. Dan Miller of the WGS to appraise the newly discovered district south of Laramie. I ended up mapping the State Line district, found 9 diamond-bearing kimberlites my first 2 years & later mapped the Iron Mountain & Sheep Rock districts and the Leucite Hills lamproite field and explored for diamonds for some US companies, an Australian company and some Canadian companies. In fact, I was promoted to US Exploration Manager and later VP of DiamonEx USA for DiamondEx Ltd (see GEMHUNTER).

I found lamprophryes in Montana & Wyoming & identified several hundred cryptovolcanic structures within & surrounding the State Line that are likely diamond deposits (these remain unexplored). A few of these include Indian Guide, Twin Mountain, Happy Jack & others. I expanded my research & found similar cyptovolcanic structures in Canada & even in the Kimberley region of South Africa. I found a major district of 50+ anomalies sitting along the interstate in the US!

Photos – Above, gem diamonds from Kelsey Lake, Colorado, vegetation anomaly over kimberlite at Iron Mountain, and exposed blue ground in highwall at Kelsey Lake. Below, 14.2 ct flawless octahedron from Kelsey Lake, aerial photo over the Ekati diamond mine in Canada (one of 5 major mines developed in Canada since 1998), carbonate-stained soil over cryptovolcanic structure, and view of one of the Lost Lakes cryptovolcanic structures.

 Commercial deposits occur in placers, kimberlite and/or lamproite & I’ll bet other commercial deposits will be found in lamprophryre in the future. The diamond deposits south of Laramie were in kimberlite & placers. The kimberlites are deeply eroded & spilled millions of diamonds into the surrounding streams, but no one has ever systematically looked for diamond in the creeks (even so, diamonds were accidentally recovered in Rabbit Creek and hundreds were recovered in George Creek, and several including a 6.2 carat diamond were recovered in Fish Creek, but the rest of the streams are UNPROSPECTED!

Kimberlite is a ultrabasic, potassic igneous rock that erupts along fractures from 90 to 120 mi depths. They typically occur in very old cratons & cratonized rocks (basically ancient continental cores that consist of >1.5 billion year old granite, gneiss & schist). The magma, under pressure rises rapidly from the mantle because of the great depth & because of considerable water vapor & carbon dioxide under pressure. Some suggest gaseous emplacement velocities of kimberlite are on the order of Mach 3. The eruption is relatively cool: CO2 gas expands cooling the magma such that emplacement temperatures of 32 degree F are not uncommon. This collection of unusual characteristics results in small, circular maar-like volcanoes (without cones) & dikes that are structurally controlled.

Gem diamond with excellent characteristic trigons on surface

Things to keep in mind: kimberlite will serpentinize because of water vapor, this produces a relatively soft rock that erodes faster than surrounding country rocks & usually results in a depression with different vegetation than the surrounding rocks. These depressions may contain shallow ponds. They are structurally-controlled such that >one anomaly is often found in a line. Because of calcium carbonate in kimberlite, carbonate will leach out into the pond staining the soil white. Keep in mind that salts are not all that uncommon in basins where lots of young sedimentary rocks occur with considerable carbonate. But in the craton basement (i.e., mountain ranges of Wyoming) there is no known source for carbonate, so if you spot a structurally-controlled lake surrounded by salt in old Precambrian rock, you might want to find out why? And if you find one, typically, with effort, you will find others along the same structure.

Diamonds found in Colorado & Wyoming ranged from microdiamonds to 28.3 cts & included one chip from a 80- to 90-ct stone. Some believe there are no commerical deposits in this area, but all mills were so poorly designed they rejected all diamonds of any size. For example, the Kelsey Lake mill rejected anything weighing >40 cts! It also rejected most diamonds under 40 cts such that when the tailings were tested in 1997, the first sample yielded a 6.2-ct stone! The grades of several kimberlites were high, the gem:industrial ratios were good & diamond values were reasonable. The biggest problem with the State Line district was good diamond companies with diamond expertise were in short supply.

Indicator-Minerals

CAPE RUBIES, CAPE EMERALDS, GARNETS

Diamonds were discovered in Wyoming & Colorado in 1975 by Mac McCallum, Chuck Mabarak & the USGS. This lead to some exploration for diamonds. Associated with diamonds are a host of extremely rare mantle nodules & gemstones known as Cape Ruby (pyrope garnet), Cape Emerald (chromian diopside & enstatite) that are always overlooked by mining companies. Yet these are very attractive, value-added gemstones. With some marketing skills, could potentially capture large parts of the colored gemstone market. For example, many Cape Emeralds are much more saturated & beautiful than emerald.
These gems were found by many prospectors and geologists all over Wyoming & northern Colorado. Large areas in the Green River & Bighorn Basin contain these diamond indicator minerals, yet little exploration has ever occurred for these or their source rocks.
Photos – Diamond indicator minerals from Sloan kimberlite, Colorado, & faceted pyropes from Green River Basin, Wyoming & Kyanite Eclogite from the Aultman 2 kimberlite, Wyoming.

WMS-LightningRidgeBoulderOpal1

OPAL

A rockhound from Riverton mentioned opal south of town. The Cedar Ridge deposit lies along the highway & is cut by numerous oil field roads, no one had recognized that this place had one of the largest opal deposits on earth! A few old geological reports from 50 years ago briefly mentioned opal, so I was surprised to find opal scattered over 14 mi2, opal masses >79,000 cts along the edge of the road & common, fire & precious opal with scattered Sweetwater agate & some of the nicest decorative stone on earth. All within Tertiary age volcaniclastic sedimentary rocks that had a notable contribution of volcanic ash erupted from Yellowstone in the geological past.

This gave me a clue – nearly all of Wyoming was blanketed by volcanic ash (as was Nebraska and South Dakota). Guess what? There are other opal fields waiting to be discovered. So I found millions of carats of common & fire opal & traces of precious opal (including black opal) that suggest as soon as someone digs, valuable veins of precious opal will be found as depth!
Photos show precious opal, Sweetwater agate, cobbles of opal in oil field adjacent to road. Below are fire and common opal