“The artificial ring structures made of broken stalagmites now have been dated by uranium series dating as 176.5 (±2.1) thousand years old, with 2σ uncertainties (95.5% probability). There are two annular structures, one 6.7 by 4.5 metres (ellipse major/minor axes), and the other 2.2 by 2.1 metres (ellipse major/minor axes), composed of one to four aligned layers of stalagmites, with some small pieces placed inside the layers to support them. Some stalagmites were placed vertically against the rings, possibly as reinforcement. There are also four stacks of stalagmites measuring between 0.55 and 2.60 metres in diameter, two of which were inside the large ring and two outside it. Approximately 400 stalagmite pieces (called “speleofacts” by the researchers) were used in the construction of the structure, with a total length of 112.4 metres and weight of approximately 2.2 tons.”
Yesterday I learned about Bruniquel Cave in France.
Neanderthals broke off stalagmites and stalactites and used them to create a structure in a cave almost 200,000 years ago.
https://en.m.wikipedia.org/wiki/Bruniquel_Cave
“The artificial ring structures made of broken stalagmites now have been dated by uranium series dating as 176.5 (±2.1) thousand years old, with 2σ uncertainties (95.5% probability). There are two annular structures, one 6.7 by 4.5 metres (ellipse major/minor axes), and the other 2.2 by 2.1 metres (ellipse major/minor axes), composed of one to four aligned layers of stalagmites, with some small pieces placed inside the layers to support them. Some stalagmites were placed vertically against the rings, possibly as reinforcement. There are also four stacks of stalagmites measuring between 0.55 and 2.60 metres in diameter, two of which were inside the large ring and two outside it. Approximately 400 stalagmite pieces (called “speleofacts” by the researchers) were used in the construction of the structure, with a total length of 112.4 metres and weight of approximately 2.2 tons.”
Not sure if Wikipedia article excludes pictures intentionally, but they can be found under references here. For example:
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I think you missed attaching the pic, but I’d love to see it!
@jordanlund It’s visible to me. Hmmm. I’ll attach it again, or a different one. Thanks.