The title is more general than my particular question, in particular I bought a "allen key" and it broke after doing a lot of force with it trying to turn a hard screw. In order to get a harder tool I need to know the material of this one. Tell me how to test if this allen key is chrome vanadium. If i should weight it, measure volume thus density, and this picture:
broken allen The other broke like this, it deformed:
I want to be also a little educated on this topics: probably the tool is chrome vanadium but of low quality, or maybe it is extremely expensive or hard to test for me if the new tools I bought are of another material and if it's harder than the broken ones, the new ones are chrome vanadium and "stanley" (a corporation).