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Block of barite (barium sulfate) breccia (angular broken rock), consisting of fragments of arkosic redbed sandstone with fracture porosity filled by quartz and barite. Conjugate fractures aligned both parallel to the base of the specimen, and rising to left.  Portions are mineralized, indicated by blue (malachite?) and heavily oxidized fracture (lower left).

Host Rock: Sedimentary. Sandstone. Arkose.  Fracture Filling: Hydrothermal. Vein.

Triassic red sandstone of the New Haven Formation of the Newark Supergroup was fault-fractured into a breccia during peak rifting, mainly along high-angle normal faults.  The fracture porosity filled with hydrothermal veins precipitated by aqueous magmatic fluids, mainly quartz and barite.  Likely from the Jinny Hill mines in Cheshire, CT, where barite ore was mined in the 19th century.

~200 million years old (Ma)

Symbolizes the dynamism of crustal rifting and volcanism near the time of the one of Earth's major extinction during the time of early dinosaurs as Pangea was being rifted apart.

Link to State Geological Map from USGS.  Link to State Geological Survey.

Hartford Courant article says specimen came from deep in the Jinny Hill mine.

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