This is a classic jar by Alice Cling.  It has narrow shape with a square mouth.  The entire jar is fully polished and then it is outdoor fired and the variation in the color is from the smoke and fire.   The fire clouds on this jar range from deep red to black.  The piece was covered in pine-pitch after the firing, a continuation of the traditional Navajo pottery when the pitch was used to make the pottery waterproof. Alice has won numerous awards for her pottery and been featured in books such as “Legacy of Generations.”