Balisong Gallery G Bonus

Notice the dimple between the two tang pins. It's closest to the tang pin on the left.

 That dimple is the scar left behind by a Rockwell hardness test.

Most custom knife makers simply rely on their process controls to 
produce repeatable hardening.  Mr. Guinn, however, tests each blade
individually.

You can read more about heat treatment and blade hardness in class notes by
our own noted balisong authority, Professor Roland Phlip of the Institute for 
Advanced Balisong Studies.  Click on the icon below