Here is a fantastic Nevada trilobite double with an excellent Nevadia weeksi as well as a very rare Esmeraldina rowei.  The Nevadia weeksi offers an excellent and detailed preservation. The Nevadia is about 38 mm long. The Esmeraldina rowei presents itself from the ventral side. So you look into the trilobite from the underside of the carapace. The Esmeraldina measures about 35 mm in length.
Both trilobites alone are already rarities, having both species together on one plate is exceptionally rare. 

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