Quote Originally Posted by eKretz View Post
Voids and free space aren't there in a black or translucent Ark. Not enough to do anything anyway. I can see single digit micron scale with my scope and there are no pores visible on any of my black or translucent stones. SiO2, quartz, silica, silicon dioxide - these are all the same thing in slightly different physical form. There are pores/free space in the less dense Ark stones I.E. Washita - and those are certainly influencing cutting properties.
Take a look at this page in the right hand side you will see a picturre of three arkies read below the picture about the the space and pores and loading .
Novaculite: Used for making stone cutting tools and sharpening metal blades.