Color:  Sentinel Butte Porcellanite is a light green color.

Texture: 

Luster:

Silica Fabrics / Fossils:

Patina:

Heat Treatment: 

Knapping: 
 

 

 

 

 

 

 

 

 

 

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Distribution Comments:

Sentinel Butte Porcellanite is associated with the Sentinel Butte Shale Member of the Fort Union Formation of southwestern North Dakota to northeastern Montana.  Primary outcroppings occur in Sentinel Butte, Golden Valley County, North Dakota.