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Escher and Thuringian are German stones...
All Escher's are Thuringian stones, but Thuringians are not Escher.
Escher is basically a brand name of Thuringian....

Looks like (Looks Like) a big fat Escher to me, or Thuringian?
If so, Awesome find. It looks like, and it's hard to tell in pics, but there may have been a label on the end at one time, like...