Species: Olenellus gilberti
Age: Lower Cambrian
Formation: Pioche Shale
Locality: Lincoln County, Nevada
 
This an incredible example of the classic American trilobite species Olenellus gilberti.  The trilobite is stained orange by iron oxide inclusions and is sitting against a pink matrix covered with branching, tree-like dendrite crystals.  The trilobite measures 6.4 cm long  including telson and 4.2 cm  wide across the genals.  The matrix measures 19 x 13 cm (7.5 x 5 inches).