They're around six inches long. I've been charging $5. They're stainless steel. They're not heat treated, I'm not even familiar with heat treating steel!
As for guns being the primary weapons of our society, I doubt very much that if you walk into a crowded bar anybody will have a gun, but several people will probably have knives. Many knives I've seen sold in stores, including those in the $50+ range, break during combat! I'm not saying any of the knives here do (although wood/bone handles tend to break in combat) and folding knives frequently break on the fold. At least my shivs don't break in combat.
To be on topic; I think that we've almost achieved a peaceful society. There is very little fear of violence when going about a persons' daily activities, especially if one is careful. Assault weapons, or tools that are designed to kill or cripple humans, are very rare. I hope to perfect my weapon crafting, and eventually craft weapons such as firearms, tanks, missiles, and hydrogen weapons systems. (Maybe not that last one

) Is it responsible of me to bring these things to the (black) market, knowing that in our peaceful society nobody has human-destroying tools? There was a stabbing recently in my home town, and the knife broke during the stabbing. Good thing that wasn't a good assault knife! On the other hand, weapons may be an important part of being human and thinning the herd? I'll think about it more carefully, especially if I ever progress to uncommon weapons that have the power to kill many humans in a short amount of time...