The Tucson Gem, Mineral & Fossil Showcase is the biggest show of its kind in the world. I’ve always wanted to go, and this was the year! Hold on to your hats (and wallets) as we fly to Arizona.
Sharon Lyon
Editor, GeoLifestyle
Tucson Gem, Mineral & Fossil Showcase
Me with a T-Rex skull cast at the 22nd Street Show
The Tucson Gem, Mineral & Fossil Showcase takes place from late January through mid-February. More than 65,000 visitors come from all over the world to buy, sell, and trade specimens. There are more than 50 shows at multiple venues! How does one prioritize what to see?!
Here’s where I went:
Our first show was the highly rated 22nd Street Show, situated inside two massive tents. With more than 300 vendors, we were overwhelmed by the huge selection of minerals, gems, fossils, meteorites, beads, and jewelry. You could buy a model of a T. rex skull, a real woolly rhinoceros skull, or one of the most beautiful amethyst geodes I’ve ever seen. A word to the wise: If you are unsure of a purchase, continue a few booths down the aisle. You’re bound to find what you want at a better price… And don’t be afraid to haggle!
The Co-op Mineral & Fossil Galleries is an indoor venue, known for its 11 galleries with displays rivaling the best museums. Fossils included ammonite blocks, Green River fish, crocodiles and turtles, a mammoth skeleton, and huge, dining-room-table-size slabs of polished petrified wood. Intricate spiny trilobites, dinosaurs, a sloth skeleton, and a Dunkleosteus (Devonian armored fish) skull sat next to towers of copper, malachite, and rose quartz. Prices were surprisingly reasonable for small fossil purchases.
The Rock Yard was exactly what it sounds like—barrels of minerals and rocks on pallets in a lot. Specimens were varied and colorful, so it was a bit like a geologist’s birthday party. Sadly, the sizes were too large for my suitcase.
TheKino Gem & Mineral Showwas located adjacent to the Kino Sports Complex and had more than 200 exhibitors, showcasing everything from amethyst slices and geodes to agate fountains and beautiful jewelry from across the globe. This show was indoor-outdoor and was the last show we attended, so we lost our heads over some variegated calcite.
A message from AAPG and MicroSeismic
In continued celebration of International Day of Women and Girls in Science on February 11 and the upcoming International Women's Day on March 8, AAPG and MicroSeismic are showcasing interviews from women leaders. This week's featured leader is Karen Foster, vice president of geoscience at Shell. Here is a sneak peek from her interview:
“I love seeing so many aspects of geoscience being applied across the industry, from frontier exploration, right through to decommissioning and underground storage... Every project or study is different, and we’re constantly learning and gaining new information through our activities.”
The Tucson Gem and Mineral Show, known as the Main Show, was held for four days in the Tucson Convention Center. Organized by the Tucson Gem & Mineral Society, this year the show celebrated its 70th anniversary, making it the oldest and most famous show in the world.
The theme this year was the color green, so emeralds, malachite, epidote, and green fluorite were among the featured displays.
The Main Show was best for observing the exhibits, which covered roughly a third of the convention center floor. Vendors on the sides offered museum-class minerals, jewelry, fossils, and rock art.
We attended on a Friday, and it seemed every school-age student in Tucson had arrived to complete scavenger hunts and crack open geodes.
Bottom line: Overall, I was amazed at the fabulous extravaganza that is the Tucson Show and would recommend it as a bucket list item for any geologist. Bring your most comfortable shoes, water, and lots of cash with you.
Can You Identify This Fossil?
I’m usually pretty good at identifying fossils, but this one stumped me. The vendor could only tell me that it is Cambrian. Any thoughts? Email editorial@aapg.org with your ideas. I can't wait to hear them!
While You're There... Visit the ASARCO Mineral Discovery Center & Copper Mine
This mine truck holds 300 tons of rock (me for scale).
Arizona produces approximately 65 percent of our country’s copper. Travelers can tour the ASARCO Copper Mine, located in Sahuarita, Arizona 23 miles south of Tucson.
About the mine and its deposits:
The current mine is 2.5 miles long, 1.5 mile wide, and 1,200 feet deep, and is situated on 20,000 acres.
The intrusive event responsible for Arizona’s porphyry copper deposits occurred about 70 million years ago. The copper deposits formed from metal-bearing fluids expelled from porphyry-forming magma. When the fluids interacted with heated groundwater, it yielded a corrosive liquid that chemically altered rocks adjacent to the intrusion.
The metal deposits were later exposed by faulting and erosion. Weathering processes oxidized associated pyrite (iron sulfide), dissolving it in rainwater to form an acidic iron sulfate solution that dissolved the main copper-ore mineral, chalcopyrite (copper-iron sulfide). The dissolved copper was redeposited and concentrated, principally as the mineral chalcocite (copper sulfide).
Porphyry copper deposits commonly yield molybdenum and silver as co-products.
My colleague Rasoul Sorkhabi recently discussed porphyry copper deposits and plate tectonics in more detail in his weekly newsletterCore Elements(if you haven’t subscribed, and you want to see the latest geological studies, you should sign up!).
How to visit: Take the self-guided tour of the ASARCO Mineral Discovery Center’s indoor and outdoor exhibits and watch the featured video, which walks you through the copper transformation process. Afterward, join the mine tour to see the mining and refinery processes.
Many thanks to GeoLifestyle readers Glenn Felderhoff and Jeff Spencer for sharing their thoughts on which shows to visit in Tucson. Next week, we’ll continue with some other fun geo-sites outside of the city.
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