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We at KeepsCache have for you a beautiful world-class, museum-grade specimen of Limonite after Marcasite Pseudomorph. This massive centerpiece was recovered from the Fortress Keep Mine in Jefferson County, Missouri.
Weighing in at a substantial 2 lb 15.4 oz, this is an exceptionally large and bulky example of the rare \"Jack Straw\" crystal habit. While smaller pieces of this material are occasionally found, it is incredibly rare to find a specimen of this mass where the delicate, needle-like lattice remains in an \"extremely perfect\" state.
The specimen measures 6\" x 5\" x 4\" and features a dense, complex geometry of crisscrossing crystals. The pseudomorphic process has perfectly replaced the original Marcasite with Limonite while preserving every sharp angle and structural detail of the original \"haystack\" formation.
Specimen Details:
Locality: Fortress Keep Mine, Jefferson County, MO
Weight: 2 lb 15.4 oz (Nearly 3 lbs)
Dimensions: 6\" x 5\" x 4\"
Habit: Jack Straw Pseudomorph
Condition: Extremely Perfect / Museum Grade
Seller Note:
This is the premier piece of our current inventory. Its sheer size and weight, combined with the pristine condition of the fragile Jack Straw structure, make it a top-tier specimen for serious collectors of Missouri minerals or pseudomorphs.
![Huge 6\](img-large/g/R08AAeSwjIZo8UYK/s-l1600/Huge-6-Jack-Straw-Limonite-Marcasite-3lb-Fortress-.jpg "Huge 6\")
