Category: Mazon Creek
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Fossil Friday #298: Seed Fern Fiddlehead – Spiropteris
This is the “Fossil Friday” post #298. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This week’s Fossil Friday features a fiddlehead — the coiled…
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Mazon Monday #302: The Wreck of the 5560
The Marion Power Shovel Company was an American company that designed, manufactured, and built steam shovels, power shovels, blast hole drills, excavators, and dragline excavators. The company was headquartered in Marion, Ohio and operated from 1884 to 1997, when it was acquired by its competitor Bucyrus International, Inc. Marion-built shovels and other products were among…
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Fossil Friday #297: Alethopteris serlii
This is the “Fossil Friday” post #297. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This week’s Fossil Friday is a favorite of many…
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Throwback Thursday #297: Season’s Greetings from the Langfords!
In 1939, their Christmas card included a photo of the “Fossil Gardens of Northern Illinois”. The picture is a view of the strip mines about 1 mile south of Wilmington, IL, at a place that was not far from where Cinder Ridge Golf Course is today.
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2026 ESCONI Gem, Mineral, and Fossil Show – Preview #1: Tully Monsters
This is the preview post #1 for the 2026 ESCONI Gem, Mineral, and Fossil Show Live Auction. The ESCONI Gem, Mineral, and Fossil Show for 2026 will be held on March 21th and 22nd at the DuPage Fairgrounds in Wheaton, IL, which is the same location as last year. All details can be found here.…
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Mazon Monday #301: Cordaianthus ovatus
This is Mazon Monday post #301. What’s your favorite Mazon Creek fossil? Tell us at email:esconi.info@gmail.com. Cordaianthus ovatus is thought to be the fertile structure for Cordaites borassifolius (see Mazon Monday #299), an extinct genus of early gymnosperms. Cordaites probably grew to more than 100 feet tall in swampy conditions, forming forests similar to modern day mangroves. Cordaianthus…
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Fossil Friday #296: Roachoid Wing from the Creek
This is the “Fossil Friday” post #296. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This beautiful roachoid wing was collected from the Mazon…
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Mazon Monday #300: Mazon Creek horseshoe crab fossil shows evidence of ancient algal or parasitic infestation
This is Mazon Monday post #300. What’s your favorite Mazon Creek fossil? Tell us at email:esconi.info@gmail.com. The Lauer Foundation just won’t let the Mazon Creek horseshoe crabs alone… first it was Euproops danae remains in bromalites (see Mazon Monday #283), now they’ve found evidence of ancient algal or parasitic infestation in another Euproops danae fossil from the…
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Fossil Friday #295: Juvenile Dvinosaur From Mazon Creek
This is the “Fossil Friday” post #295. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! We have a particularly special Mazon Creek fossil to share…
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Mazon Monday #299: Cordaites borassifolius
This is Mazon Monday post #299. What’s your favorite Mazon Creek fossil? Tell us at email:esconi.info@gmail.com. Cordaites borassifolius is an extinct genus of early gymnosperms. Cordaites probably grew maybe 100 feet tall in the drier areas of the Carboniferous swamps. They had stilt-like roots, forming forests similar to modern day mangroves. Cordaites is relatively rare in the Mazon…
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Fossil Friday #294: Phenopterum briggsi
This is the “Fossil Friday” post #294. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Phenopterum briggsi is a grylloblattidan species of insect from the…
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Mazon Monday #298: The Freeze/Thaw Method
With winter arriving this weekend, it’s the perfect time to set out a few containers of Mazon Creek concretions and let nature do the work. Many collectors take advantage of the season’s freeze/thaw cycles to speed up the opening process, by placing buckets or smaller containers of nodules gathered throughout the year outside to weather…
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Mazon Monday #297: Pit 11 Coal Mining Artifact
This is Mazon Monday post #297. What’s your favorite Mazon Creek fossil? Tell us at email:esconi.info@gmail.com. We often focus on the beautiful fossils found in the Mazon Creek deposit, but sometimes overlook the rich history that surrounds them. Coal mining played a central role in shaping the Wilmington, Braidwood, and Coal City area, from the deep…
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Fossil Friday 292: Annularia inflata From the Past
This is the “Fossil Friday” post #292. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Michele Micetich, curator at the Carbon Hill School Museum in…
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Throwback Thursday #292: Isabel Bassett Wasson… revisited
This is Throwback Thursday #292. In these, we look back into the past at ESCONI specifically and Earth Science in general. If you have any contributions, (science, pictures, stories, etc …), please send them to esconi.info@gmail.com. Thanks! email:esconi.info@gmail.com. You may remember Throwback Thursday #284, where we discussed Isabel Bassett Wasson. Wasson (1897-1994) was one of the…
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Mazon Monday #296: Jim Turnbull in Pit 11
Jim Turnbull, namesake for Anthracomedusa turnbulli (see Mazon Monday #278), worked for Abbott Labs for many years. Abbott has/had an internal newsletter called “AbbotTopics”. In the October 8th, 1965 edition, Jim is the subject of an article titled “Prehistoric Insect Discovery May Bear Abbott Man’s Name”.
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Fossil Friday #291: Carboniferous Fish in Black Shale
This is the “Fossil Friday” post #291. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This week’s Fossil Friday is a detailed Carboniferous fish fossil…
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Mazon Monday #295: Ida Thompson collecting in Pit 11 in 1968
Michele Micetich, curator of the Carbon Hill School Museum, provided the photos in this post. The photos are part of the Tom Testa collection at the museum. On the back of the photos, there are notes written by Ida Thompson to Melbourne McKee, a chemist for the Peabody Coal Company in the Coal City area.…
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Fossil Friday #290: Cyclopteris orbicularis
This is the “Fossil Friday” post #290. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! We have a beautiful Cyclopteris orbicularis from Knob Noster for…
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Mazon Monday #294: Montceau-les-Mines
This is Mazon Monday post #294. What’s your favorite Mazon Creek fossil? Tell us at email:esconi.info@gmail.com. Montceau-les-Mines is a commune located in the Saône-et-Loire department of the Bourgogne–Franche-Comté region in eastern France. It lies southwest of the city of Dijon and today has a population of just under 20,000 people. The town was officially established on…
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Fossil Friday #289: Asolanus camptotaenia bark from the Mazon River
This is the “Fossil Friday” post #289. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Recently, George Witaszek sent us photos of a rare Mazon…
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Mazon Monday #293: Mazon Creek Project Slides
The Mazon Creek Project was a program sponsored by Northeastern Illinois University. Founded in the 1960s, by the late Eugene Richardson Curator of Fossil Invertebrates at the Field Museum in Chicago Illinois. It was originally an attempt to encourage more communication between paleontologists and amateur collectors. After Peabody Coal Company sold Pit 11 to Commonwealth…
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Fossil Friday #288: Danville Roachoid Wing
This is the “Fossil Friday” post #288. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Andrew Young sent us photos of a beautiful Roachoid wing…
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Mazon Monday #292: Mazon Creek Fossil Day 2025
We had a nice turnout at the Mazon Creek Fossil Day event in the Coal City library a few weeks ago. There were multiple displays by members and people brought in some of their finds for identification. Last week’s Fossil Friday was an absolutely beautiful shark egg case (Palaeoxyris multiplicatum, see Fossil Friday #287).
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Fossil Friday #287: Palaeoxyris multiplicatum
Hunter Nettles brought an absolutely breathtaking specimen of Palaeoxyris multiplicatum to the Mazon Creek Fossil Day. This specimen was found last year (2024) in the Pit 1 locality of Mazon Creek.
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Mazon Monday #291: Dithyrocaris sp.
Dithyrocaris sp. is a genus of crustacean from the Carboniferous. The Mazon Creek fossil biota includes one undescribed species, although there are other described species from other fossil localities – Bear Gulch, Montana (Dithyrocaris rolfei). Danville, IL (Dithyrocaris carbonarius), Cane Hill, Arkansas (Dithyrocaris quinni), the Allegheny Group, Ohio, and localities in Europe.
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Fossil Friday #286: Rhabdoderma exiguum
This is the “Fossil Friday” post #286. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! For this week’s Fossil Friday, we have a Rhabdoderma exiguum.…
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Reminder: 2025 Mazon Creek Fossil Day, October 11th, 2025 at the Coal City Library
The 2025 Mazon Creek Fossil Day will be held on October 11th, 2025 at the Coal City Library from 10 AM to 3 PM. See you there! Previous events
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Mazon Monday #290: Danville Spoil Pile Trip Report for September 2025
This is Mazon Monday post #290. What’s your favorite Mazon Creek fossil? Tell us at email:esconi.info@gmail.com. There was lots of fun on the field trip to the Danville Spoil Pile on Saturday, September 27th, 2025. The day was hot and dry with a clear sky and temperatures in the 80s… summer like weather in late September…
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Fossil Friday #285: Palaeoxyris lewisi
This is the “Fossil Friday” post #285. Expect this to be a somewhat regular feature of the website. We will post any fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! We have a beautiful Palaeoxyris lewisi shark egg case…