Color:  Plattsmouth Fossiliferous Chert ranges in color from a light gray to medium or medium dark gray or brownish gray or almost black.  Broad faint mottling may be present.  Light brownish fossils form specks of off-white to light gray and brown.

Texture: Fine grain

Luster:

Silica Fabrics / Fossils: Abundant including; fusilinid, crinoid columns, and bryozoa

Patina:

Heat Treatment:  Heat treatment produces little notable changes.

Knapping: 

 

 

 

 

 

 

 

 

 

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Distribution Comments:

Plattsmouth Fossiliferous Chert is associated with the Plattsmouth Member of the Oread Formation, Virgilian series of Iowa.  Primary outcroppings occur in Adair, Montgomery, and Cass counties, Iowa.