State by State


  • Specimen Number


  • Description

    Rough block of gray granodiorite. Identified by survey staff.  Filled fracture from lower right to upper left suggests contraction during cooling.

  • Classification

    Igneous.  Plutonic. Granitic. Granodiorite.

  • Location & Occurrence

    From the "State of Washington's new tunnel," as described in the 1937 Hartford Courant. Search indicates that the "New Cascade Tunnel" was a railroad tunnel through Stephen's Pass of the Cascades east of Seattle that was dedicated in 1930 as a great wonder, drawing national attention.  Formation name not known.   A Cascade Range batholith.

  • Geologic Age


  • Geoheritage

    Andes style arc magmatism.  The newspaper description provided the clue to where in the state it was from..

  • Links

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

  • Other

    The Washington Geological Survey provides an example for the rest of the nation.

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Specimen stone for Washington.
Closeup of Washington stone.e Outline Map of Washington. Geol Map of Washington.