This trilobite is a rare Ogygopsis elongata from the Metaline Formation of Washington. The middle Cambrian Metaline  Foramtion of Pend Oreille County in washington state is largely equivalent to the famous Stephen Formation of the Burgess Shale of British Columbia. The strong tectonic stress of the sediments does not make the collecting conditions easy.   However, the general rarity of trilobites from the state of Washington should  be remembered here.
This trilobite is a good and representative find from an very unusual site.

 

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