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Roger Weller, geology instructor

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novaculite
by Rebecca Bowser
Physical Geology
Fall 2011                  

                                     ARKANSAS SHARPENING STONES

         
wood carving by Clay Bowser                                                                  
 

In order to carve between the tiny spaces of the detailed flowers and leaves, Clay Bowser had to keep his wood carving tools sharpened and polished. When each of his carving tools became dull, he simply rubbed the blade a few times against a special sharpening stone that honed and polished his tools. These sharpening stones, which are also called whetstones, are not just ordinary stones one would find in their backyard, unless this person’s backyard was in Arkansas, one of the places where the stones are mined. In fact, the “unique” name geologists gave to this type of sharpening stone is the “Arkansas Sharpening Stone.”  Arkansas sharpening stones are very popular among the woodcarving community because woodcarvers such as Clay know that these stones add more life to their woodcarving tools and, unlike electrical sharpening tools, won’t remove as much metal from the blade. Since Arkansas Whetstones are rated the best for sharpening metal blades, the question is: What makes these stones so popular?
 

                    Photo by Norse Woodsmith

WHAT IS NOVACULITE?

                    
  Black novaculite boulder along stream in the Ouachita Mountains of southwestern Arkansas. Photo by Bill Martin.
 

What makes Arkansas Sharpening stones so popular for woodcarvers? The answer is that these stones contain the rare mineral novaculite, which derives its name from a Latin word, novacula, and is defined as “sharp knife” or “razor stone.”
 

                                                                                            
 Novaculite comes in different colors. Photo by Diane Rose Angelo

Not only does novaculite “sharpen” knives or woodcarver tools, but also, these rocks have sharp edges when chipped. When a novaculite rock is broken or chipped, it breaks into a smooth conchoidal (shell-like fracture). Native Americans used the chipped pieces to make their razor-like spearheads, dart points, and arrowheads. 

                             
Photo of Novaculite Indian Artificats Courtesy of Antique Helper Dan Ripley.

Novaculite is a sedimentary rock composed mostly of microcrystalline quartz and is a recrystallized variety of chert. Novaculite has a hardness of seven, is dense, hard, white to grayish-black in color, translucent on thin edges and has a dull to waxy luster.