Mostly beyond the scope of this board, but start with file test of steel and with grinder sparking test. Look these up in reference material and if you can't find anything, I'll check for some reference works. Heat treating small parts with a torch is simple in principle, but requires some skill and learning in practice. Basically you heat the part above the steel alloy's critical temperature and quench in a bath designed to cool at a rate compatable with the alloy's hardeneing characteristics. Then, you may well temper by reheating to a lower temperature. The glow color of the steel is a indicator of temperature for hardening and the oxide colors for temper. This is easier if you have access to a heat treating oven, but you most likely don't. Again read some reference works on doing it by hand in a small shop. Craftsmen have been doing this for a long time, so it can be done.
