|Industrial and gem-quality macro-diamonds collected from|
Wyoming kimberlites along Highway 287 south of Laramie.
This larger diamonds were extracted from kimberlite a about
5 years after the first micro diamonds were found in the area.
|Kimberlite specimens containing hidden diamonds along with|
visible chromian diopside and pyrope-almandine garnet gem
megacrysts. Sloan Ranch kimberlite, Colorado. Kimberlite is
considered to be one of the rarest rock types on the earth's
|A 24,150-carat iolite rough gemstone from Grizzly Creek. This giant, is actually tiny, when compared|
to some of the larger iolites sitting in outcrop that are estimated to weigh more than one million
Possibly, the greatest gemstone discovery in Wyoming occurred in 1995, and led to similar discoveries in 2004 and 2005. In 1995, the author went looking for the source of a rock collected by Wyoming Geological Survey Industrial Minerals Geologist, Ray Harris (RIP). Garnet was misidentified in the sample, but instead, these red gems had characteristic crystal habits of corundum. After getting the location of the sample site from Harris, the author examined the Palmer Canyon locality in the Laramie Mountains for ruby and sapphire. Sure enough, some high-quality specimens of ruby and sapphire (both varieties of corundum) were recovered from the vermiculite schist. And while searching the area for other outcrops of corundum, gem-quality kyanite, and also gem-quality iolite (cordierite, also referred to as water sapphire) was found including a large, 1,714-carat, fist-sized rough gemstone of the highest quality! Palmer Canyon was a poly-gem deposit.
|A 1,720-carat iolite gemstone rough collected at Palmer Canyon|
|Grizzly Creek outcrop containing |
hundreds of thousands of carats of iolite.
|One of the first olivine grains faceted showing |
excellent transparency. Leucite Hills, Wyoming
After a little searching and some mapping in Wyoming's lamproite volcanic field near Rock Springs, known as the Leucite Hills, sure enough, not far from Black Butte lamproite, I came across two green anthills. Wow, I was excited, here were two anthills that had so many specimens of olivine, that they were green - I examined the olivine with my 10x hand lens, and whazzooo!!! They were mostly gem quality! This was amazing! Since the late 19th century, geologists visiting the field had reported some olivine, but never in concentrations like this, and also, not one had even mentioned these minerals were gem-quality. Talk about wearing blinders when going to the field. So, I collected the two anthills, these were later processed in our laboratory, and more than 1,300 carats of gem-quality peridot were recovered. Why, thank you ants! But, didn't find any diamonds, but at the same time, to find diamonds, typically large bulk samples must be taken with a bulldozer - not the kind of money that we had for research. But a couple of chromites recovered from a couple of lamproites had favorable chemistry for diamonds. So, Wyoming just needs to get someone interested in digging diamonds near Rock Springs.
|A group of raw and faceted olivine (peridot) collected from anthills in the Leucite Hills, Wyoming|
discovery by the author.