Coaldale Crater Gemstones, Meteorite Impact Produces Rare Specimens Options

[ASTROBLEME]

Members and Guests of Colorado Prospector,

Many years ago I discovered a highly eroded, geologically complex and very ancient impact crater centered 3 ¼ miles northwest of Coaldale, Colorado (USA). I am announcing this discovery as a long-time contributor to this forum in an effort to assure that the public has access to this information. Dan (the owner and operator of Colorado Prospector) is preparing some of my "Coaldale Crater" specimens for jewelry settings. He has graciously agreed to document his work progress so that others can gain a better understanding of the effort it takes to transform these raw materials into valuable gemstones. Please take time to follow this project along the way. I hope you find the subject interesting.

I'll be sharing the science behind this amazing discovery as our work progresses. This research builds upon my work at Gunnison Crater, Westcliffe Crater, Silver Cliff Crater and Hillside Crater that proved an extension to the 38th Parallel Crater Chain dating to the Late Devonian Period. Although the Coaldale Crater is also along the 38th Parallel, it is not part of the well documented crater chain system. My efforts in the Coaldale Colorado region included collecting field survey data, acquiring and analyzing numerous geologic specimens followed by an extensive review of the relevant scientific literature. The results support an impact event that occurred during the Oligocene Epoch.

For now, I'm providing the attached map depicting the present peak ring exposure. It is fascinating that this impact crater has survived the deep erosion and strong fault deformation that Mother Nature has provided continually over the past 27+ million years.

Sincerely,

ASTROBLEME

[ASTROBLEME]

Dan,

I am so impressed by your ability to cut those thin sections. Your efforts will help with investigating the chondrules further. Many thanks for preparing those slices.

Members and Guests,

The majority of chondrules in the Coaldale Meteorite are similar to other meteorites but those thin rimmed, blue-green hued, glassy chondrules are distinctly different. The spherical inclusions are not to be confused with a secondary infilling process that occurs in some volcanic deposits. Only a handful of meteorites in current collections have any "glassy" chondrules. These unique blue-green glass rich chondrules are the source for my father's gemstone find. Of significant interest is the fact that I've found a limited number of cavities that I call "sockets" in some broken fragments of the Coaldale Meteorite. A few "sockets" are quite large...and I interpret those cavities to be the source of the exotic gemstones such as my dad's...and with deposits found in the Red Rock Placer Mining Claim Group that I've located on the Arkansas River where it cuts through the crater.

The tektite and breccias at Coaldale Crater that Dan is preparing are basically a hyper-velocity impact melt induced reworking of the meteorite, mixing it into the deposits that were in place at the impact crater site some 27+ million years ago. Most of the meteorite was destroyed and the glassy chondrules in the meteorite were remelted and mixed up with earth material being excavated during the crater formation. The common name for this type of impact material is "tektite". Dan previously worked up the Gunnison Crater Tektite gemstones for my company several years ago. In fact, he was the first one who recognized metal inclusions within that tektite. I fully trust his ability to work on this project. I think Coaldale Tektite will have fantastic eye appeal and I'm looking forward to the shaped and polished results!

It is apparent that the meteorite creating Coaldale Crater was a large object that had coalesced from collisions in space with other bodies. Those high speed space collisions resulted in melting of the original meteorite's components to form the larger body having a much altered composition in the end. The rims of the glassy chondrules appear to contain mineral and glass compositions from the original nebular condensation components and tiny matrix grains of the smaller original meteorite(s) that had coalesced. Only recently have scientists started to investigate this type of chondrule formation. Experiments using NASA’s two-stage light gas gun to analyze thermal and shock alteration due to hypervelocity impacts into variable materials is currently underway.

I am still months away from finalizing the all data from this meteorite impact. One thing that might interest readers of this thread is the results of the chemical test I developed for fast and cheap determination for “meteorite or meteor wrong”. You can read about the procedure on this forum at

Meteorite Test

The attached photos show the results for that nickel test on the Coaldale Meteorite specimen.

ASTROBLEME

Acid Leaching Result



Addition of Nickel Test Reagent




Final Result