Color:  Mill Creek Chert is light brown to gray and fades into hues of red.  Colors can vary from white to light gray, gray to grayish brown, orange white to orange gray, or pale blue to black.  Concentric banding may be present.

Texture:  The grain is generally course, but finer grains do occur.

Luster: Dull

Silica Fabrics / Fossils: Not typically

Patina:

Heat Treatment:  Heat Treatment increases the hues of red and slightly increases the luster

Knapping: 

 

 

 

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Distribution Comments:

Mill Creek Chert is found in nodule form in creek beds and is associated with the Salem / Ullim limestone formation.  It is named for Mill Creek Illinois.  It is found from southern Illinois throughout the Middle Mississippi River basin.