_______________________________________
Logging Tasks – Answer These Questions to Claim This EarthCache:
Please send your answers to the cache owner via message or email. Do not post them in your log.
1. What is the diameter (total width) of the Blairmore Ring?
2. How tall is the Blairmore Ring? If the Blairmore Formation is about 60 meters (200 feet) thick, and each ring is 0.6 meters ( 2 feet ) tall, how many rings would be required to fully line that portion of the shaft at that thickness?
3. What is potash commonly used for?
4. Where does the name “potash” come from?
To claim an Earth Cache, please Upload a photo of yourself (or your GPS – face not necessary) at the Blairmore Ring to celebrate your visit.
DO NOT POST ANSWERS IN YOUR LOG. Please don’t provide the answers when logging the cache online except for the photo, for the rest of the queries use the “Send answers” feature OR geocache mail the cache owner including the earth cache GC number, title and the answers. 
Please answer to the best of your ability. As long as you give it your best effort, we'll be happy to accept your responses. You will probably find some of the answers you are looking for in this description page, or on the interpretive sign!
________________________________________
Earth Science Lesson: Potash, Geology, and Innovation Beneath the Prairies
Welcome to one of Saskatchewan’s proudest geological and industrial monuments: The Blairmore Ring. This massive cast-iron ring isn’t just a piece of metal — it’s a symbol of ingenuity, determination, and our province’s deep geological legacy.
The Blairmore Ring is:
• 5 metres (16 feet) in diameter
• about 0.6 meters ( 2 feet ) tall
• Weighs over 28,000 kg (28 tonnes)
________________________________________
What Is Potash?
Beneath much of Saskatchewan lies a treasure: a vast layer of potash, a mineral resource that plays a vital role in growing the world’s food.
Potash is a general term — it doesn’t refer to just one substance, but a group of potassium-containing compounds that are mostly used in fertilizers to help crops grow strong and healthy.
Here are the key potash compounds:
• Potassium carbonate (K₂CO₃): This is the "original" potash — historically obtained by leaching wood ashes and evaporating the solution.
• Potassium chloride (KCl): Also known as muriate of potash, this is the most commonly used potash fertilizer today and is mined extensively in Saskatchewan.
• Potassium sulfate (K₂SO₄): Another potassium-rich fertilizer, especially valued where crops are sensitive to chloride.
So, while "potash" originally referred to potassium carbonate from burned plant ash, the term now encompasses a broader group of potassium-rich materials, all essential for plant nutrition and soil health.
The word “potash” comes from the old method of extracting potassium carbonate: early farmers would burn wood, collect the ashes, and boil them in pots — hence the name “pot-ash.”
________________________________________
The Geological Barrier: The Blairmore Formation
To get to the potash, miners had to go more than 1,000 metres (3,280 feet) underground. But there was a big problem.
They ran into a layer called the Blairmore Formation, a 200–400 foot thick (approximately 60–120 metres) band of water-bearing sand, shale, and sediment. It was formed during the Early Cretaceous period. It was like trying to dig through a water-filled sponge — shafts would flood and collapse.
In early drilling attempts, this layer was under about 4.826e+6 pascal (700 psi - pounds per square inch) of water pressure. The engineers tried to seal it with concrete, but the sandy, shifting Blairmore Formation refused to cooperate. Water kept rushing in.
________________________________________
The Engineering Solution: Freeze and Ring
A breakthrough came in the 1960s, when Saskatchewan engineers tried a European method: ground freezing.
They installed 58 “freeze pipes”, each 76 meters ( 250 feet ) long, in a ring around the proposed shaft and pumped coolant at –50°F. After a year, the ground was frozen solid.
Once frozen, the crew excavated a vertical shaft and began installing Blairmore Rings — huge cast-iron rings like the one on display here. Each one was 0.6 meters (2 feet) tall. The rings were stacked to form a watertight liner inside the shaft.
This innovation was the key to unlocking Saskatchewan’s potash wealth.
________________________________________
A Legacy in Iron
The Blairmore Ring displayed here is a real engineering artifact — one of the rings used in those early shafts. It:
• Was originally placed in Rotary Park in 1965 as a monument
• Was relocated to the Saskatoon International Airport in 2002
• In 2017, was moved to the Western Development Museum, where it proudly stands today.
Its presence honours the thousands of workers who built Saskatchewan’s potash industry and celebrates a major geological and industrial achievement.
________________________________________
Earth Science Concepts Covered
• Geology of the Blairmore Formation (sediment, water-bearing layers, and pressure)
• Mining engineering (ground freezing, shaft construction, and water sealing)
• The formation, use, and origin of potash
• The role of geology in shaping economic development in Saskatchewan
________________________________________
Site Access and Permissions
This EarthCache is freely accessible from the front of the Western Development Museum (WDM) Saskatoon. Whereas, you are welcome to tour the display featuring a typical Saskatchewan town you do not need to enter the museum to view the ring or complete this EarthCache. The museum hours of operation are here. There is a sidewalk area to walk around and view the monument from all angles.
________________________________________
In Tribute
The Blairmore Ring stands not only as a physical monument, but as a tribute to Saskatchewan's potash pioneers — a group of innovators who turned geology’s greatest obstacle into a doorway to prosperity.
Next time you see golden wheat swaying in the prairie wind, remember the hidden red treasure deep below, and the cast-iron ingenuity that brought it to light.
________________________________________
Learn More
For further insight into potash mining and Saskatchewan’s geological legacy, visit the Potash Interpretive Centre in Esterhazy...and the earthcache there -
Potash Galore EarthCache GC1Y308; or the ALLAN POTASH MINE -EARTH CACHE EarthCache GCA0K15 or the EARTH CACHE- CORY POTASH MINE EarthCache GCA2WZH
Acknowledgments
Special thanks to the Western Development Museum, Saskatoon Airport Authority, and all the engineers, geologists, and miners who helped unlock Saskatchewan’s vast potash reserves. Without their persistence, innovation, and respect for Earth science, none of this would have been possible.
________________________________________
🌍💥 FTF Alert! 💥🌍
Huge congrats to BennyKidd for being the First to Find this EarthCache during Earth Week 2025! 🥇🔍
While the world celebrates "Our Power, Our Planet" this week, you’ve channeled your geocaching powers to connect with the Earth in true explorer style. 🌎💚
From deep soil horizons to global awareness, your FTF is a small but mighty tribute to the planet we all call home. Way to lead the charge—your log is now officially part of Earth Week history! April 21st to 27th, 2025🌱📍
Keep caching, keep caring—and keep being awesome.
#FTF #EarthWeek2025 #OurPowerOurPlanet #EarthCacheHero
________________________________________
The 2025 themes to celebrate 25 years of geocaching! :
- Frogs
January 28 – March 5, 2025
- Back to Nature = includes Earth Caches
March 26 – June 5, 2025
- Hidden Gems
June 25 – September 5, 2025
- Blast from the Past (25 Years of Geocaching)
October 1 – December 5, 2025
"Ways to participate:
________________________________________
Bibliography
Alberta Geological Survey. (2000). Summary of Alberta’s Industrial Mineral Potential: Potash. Energy and Sustainable Resource Development. https://ags.aer.ca/publications/all-publications/esr-2000-06
Alberta Geological Survey. (n.d.). Bulletin 021: The Blairmore Group in Southern Alberta. https://static.ags.aer.ca/files/document/BUL/BUL_021.pdfBlairmore Ring
CIM Magazine. (n.d.). Potash Production Comes to the Prairies. Canadian Institute of Mining, Metallurgy and Petroleum. https://magazine.cim.org/en/mining-the-archives/potash-production-comes-to-the-prairies-en/
Geocaching.com. (2014). GC5A0NP: Potash - Saskatchewan’s Red Gold. The original -now archived- Blairmore Ring EarthCache (when it was located at the airport). https://www.geocaching.com/geocache/GC5A0NP
J.D. Mollard and Associates (2019). A Reconnaissance Appraisal of Ground Water Potential and Development in Saskatchewan, Canada. https://jdmollard.com/wp-content/uploads/2024/06/Mollard-1965-A-reconnaissance-appraisal-of-ground-water-potential-and-development-in-Saskatchewan-Canada.pdf
Lafarge Canada. (n.d.). Project Spotlight – Esterhazy K3 Mine Construction. https://www.lafarge.ca/sites/canada/files/documents/project_spotlight_-_esterhazy_k3_mine_construction.pdf
Saskatoon.ca. (2005). Minutes of the Regular Meeting of City Council – May 30, 2005. City of Saskatoon. https://www.saskatoon.ca/sites/default/files/documents/city-council/minutes/2005/m_council_300505.pdf
Saskatoon.ca. (n.d.). Airport Industrial Land Use Policy and Local Area Plan. City of Saskatoon. https://www.saskatoon.ca/sites/default/files/documents/community-services/planning-development/neighbourhood-planning/airport-industrial-lap/airport_industrial_FINAL.pdf
Saskatchewan Mining Association. (n.d.). GeoVenture Blog Highlights. https://saskmining.ca/geoventure-blog-highlights/
Skyxe Saskatoon Airport (Facebook). (2017, March 1). The Blairmore Ring is a monument which stands in remembrance of the people who built the potash industry in this province. [Facebook post]. https://www.facebook.com/skyxe.ca/posts/the-blairmore-ring-is-a-monument-which-stands-in-remembrance-of-the-people-who-b/1318407808196098/
Wikipedia. (n.d.). Blairmore Group. https://en.wikipedia.org/wiki/Blairmore_Group
Wikipedia. (n.d.). Potash. https://en.wikipedia.org/wiki/Potash
Western Development Museum (WDM). (2019, January 31). Blairmore Ring Relocation Story. https://wdm.ca/2019/01/31/blairmore-ring/
Western Development Museum (WDM). (n.d.). Blairmore Ring Exhibit. https://wdm.ca/exhibits/blairmore-ring/