The blades are hand filed from ready made  3.4 mm Austrian Boehler Antinit KW 50 MV knife steel which is constructed for the production of surgical instruments (unless otherwise indicated).

The blades are subsequently hand sanded,  machine polished to mirror quality and hardened professionally to a hardness of 57 Rockwell.

This means a knife blade that has both toughness and a pleasant hardness that allows for easy re-sharpening. To my mind this is the ideal metallurgical compromise.

The photo below gives an impression of some of the stages involved:

 

Before hardening  my mark is hammered into each blade for autenticity as you'll see on this photo:

My mark represents a Roe Deer antler plus my initials