BLOG POST # 500 😊😊😊
In several of my Blog postings I noted that my time in graduate school at the University of Utah (1967-1970) was intellectually exciting as well as personally full of satisfaction and “what more could you ask for”. Within a 10-day stint in August 1967 I graduated with an A.M. from the University of South Dakota, drove all night to Kansas with my soon to be wife, got married, and headed to Utah with virtually no money; more grad school was waiting. I chose Utah since: 1) I wanted to live in the mountains; 2) Wyoming and Colorado rejected my applications; and 3) the NDEA Title IV Fellowship at Utah was more money than I had ever made in my life. We were still rather "poor" but found an apartment for $70 a month; however, we could only afford payments of $35 every two weeks! But, we found new friends (mostly students), and we were all in the same boat—not much money but excited about geology and our spouses (most of us were newlyweds).
Intellectually the University was an exciting place to be in the late 1960s—things, they were a’ changing in the world of geology. Plate tectonics, better then known as Continental Drift, was being discussed in every classroom. Armand Eardley had published the best-known textbook on structural evolution of North America, and it was the “go to” book in the pre-continental drift days. However, he constantly brought in external speakers to discuss the “theory” in his classes, the pros and cons.
Fridays were observed as days of field trips and/or research—we could walk to outcrops in the Laramide Wasatch Mountains bordering east campus. Evidence of Pleistocene Lake Bonneville was everywhere, and we could drive 25 miles or less to observe rocks of every geological period except the Silurian. Observing fantastic geology was an everyday experience.
Lee Stokes, my major advisor, hauled his students all over the state since his Utah geological knowledge was legendary. Jim Madsen, my mentor and friend, was pulling all sorts of dinosaurs out of the Cleveland-Lloyd Quarry in central Utah. Others, such as Dick Robison took his advanced invertebrate paleo students out to the west desert to hunt for trilobites in the Cambrian rocks. We then had to write a “pretend” professional paper for publication. It was just a great time to be a student of geology.
The U.S. Geology Survey had a small office in Salt Lake City and their geologists were tromping all over the Intermountain states. As they traversed through the City the Department tried to nab them to “present a lecture on their work.” I, and my classmates, were privileged to hear, and often meet, some of the most famous geologists in the west. I remember one of the speakers was a USGS scientist by the name of James (Jim) Gilluly. I remembered his name since the grad students were expected to constantly read journals and other professional papers (“you really need to take a look at XX paper since it may show up on your prelim exams”) and one of these papers (USGS PP 150) was authored by Reeside and Gilluly describing the sedimentary rocks of the San Rafael Swell in central Utah. Now the Swell was every softrocker’s favorite place for a field trip---and there were many. Gilluly also worked with Ralph Roberts and others in describing the Antler Orogenic Belt and the giant Roberts Mountain Thrust in north central Nevada (almost unknown events in the 1950s). But perhaps Gilluly’s most interesting paper was published in 1968-- The role of geological concepts in man’s intellectual development. Gilluly lived a long (1896-1980) and extremely productive life, and his name always sticks in my mind when thinking of those halcyon days of the late 1960s at the University of Utah.
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So, how does my reminiscing relate to minerals of any sort? Many/most readers realize that past postings often point out interesting tidbits about Utah minerals, and especially the few related to instructors at the University: check September 17, 2017, for a posting on whelanite, stringhamite, and callaghanite. Well, a thallium arsenic sulfosalt mineral named gillulyite (after the Utah geologist) is certainly an interesting mineral (if nothing else for its thallium content) and one of the rarest in Utah (and most likely in the country). It also has an interesting collecting history, and the following paragraph was picked up from Lehigh Minerals in Bountiful, Utah
“ In 1990 five members of the club, Mineral Collectors of Utah, went on a field trip to the Lulu Cut in the South Mercur Pit of the Mercur Mine in search of thallium minerals. An odd-looking red mineral that looked different than Realgar was found. Two members searched for crystals, only ever finding 3 specimens with small crystals. One of which is pictured on mindat.org . The three other collectors collected a few flats of specimens of the strange mineral with dark red cleavages. Dr Jim Wilson from Weber State was one of the three and the analysis done the next day did not match any known mineral species. Going back the following day to collect more specimens, he was disappointed and found the Barack mining operation mined through the collecting area and the new level was 30 feet below the area of the new mineral find. Nothing more was able to be collected. The mineral became Gillulyite with the Lulu Cut being not only the type locality but still the only locality to this day in the world. One collector sold his specimens at the next Denver and Tucson shows. These are the source of specimens currently held in collections worldwide. The mine geologist collected some superb Lorandites at another location at the mine but was present when the club was there and also had a few Gillulyites. Scott Klein and Rob Lavinsky handled these several years ago. I was able to acquire the specimens that Jim Wilson collected that day. These vary in size from thumbnails to large cabinet specimens.”
I have recently corresponded with Jim McEwen, the proprietor of Lehigh Minerals and amazingly he still has about seven specimens of this 30-year-old find sort of hidden away, but available for sale! They are listed on the Lehigh Minerals home page.
Gillulyite [Tl2(As,Sb)8S13] is a dark red in color like many mercury minerals, is soft at 2.0-2.5 (Mohs), has an adamantine luster that commonly tarnishes to a metallic luster. It needs to be protected from light as the mineral will turn such a dark red that it almost appears black. Crystals (Monoclinic Prismatic) are rare (some crystals shown on MinDat), and most specimens appear massive (and all are small). At Mercur, gillulyite is often associated with baryte (BaSO4), orpiment (As2S3), and realgar (As4S4). As a sulfosalt the elements in gillulyite are: a metal (thallium), a semi-metal and/or tin (arsenic + tin), and sulfur---Tl2(As,Sb)8S13.
The Mercur Mining District is on the southwest flank of the Oquirrh Mountains, one of the easternmost ranges of the Basin and Range Province, that dominates the western skyline at Salt Lake City (and also home to the famous Bingham Copper Mine). The initial mining at Mercur started in ~1870 with a high-grade silver deposit but soon faded and mining turned to cinnabar, the valuable major ore of mercury. Early miners knew that gold was present at Mercur; however, the small flakes were invisible and tied up in dark gray to black carbonaceous, silty limestone. The gold could not be extracted with traditional mercury amalgamation processes (today we know Mercur as a Carlin Type Deposit). About 1890, as the mining was about “done for” a couple of the investors decided to try a new process rumored to be effective—cyanide leaching. And it was successful for by 1897 the Golden Gate Mill at Mercur was the largest cyanide mill in the U.S. and operated until ~1913. After that date the gold production was intermittent with starts and stops by various companies. By 1983 Getty had established a very successful, large open pit with a cyanide heap leach operation. Barrick Gold acquired this operation in 1985, added some additional equipment and produced ~ 100,000 ounces of gold per year until reserves became exhausted in 1995. The mines have now been reclaimed and gillulyite is gone forever from Mercur (the official Type Locality is Lulu Cut, South Mercur Pit) and has never been located elsewhere. As for the Mercur Mining District, it was Utah’s largest primary gold mining district , “despite the fact that no gold was ever recognized in hand specimens” (Utah Geological Survey). I tried to visit the dumps in the early 2000s but was turned away by signs, fences, and “guards.”
I REMEMBER SPRING 1970
After the invasion of Cambodia in the spring of 1970. After the deaths of four students at Kent State University in Ohio on May 4, 1970, students rioted at the University of Utah. Classes were disrupted, the Daily Utah Chronicle offices were occupied, and the ROTC building was fire-bombed. On May 6, four thousand students gathered for a rally south of the Union Building. During the rally, fire broke out in an abandoned World War II building near the Union. The building was no great loss, considering it saved the costs of razing it, but a short while later 800 students marched into the Park Building and sat down (from the archives of J. Willard Marriott Library).
Was I in the above photo? No, the geology grad students were perched on the green lawn eating our bag lunches. We all had theses and dissertations to complete (I missed the spring deadline)!
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