Lead can take an edge too, and Yes, it can cut you.(dont ask)I'll tell you what happens to an edge that isn't heat treated properly. If you put too much pressure on the edge while honing, it will fold over. You know those wire edges we talk about so much. Well, imagine that, but you can feel it with your finger and see it with the naked eye.
That is the results off a 220 stone. Yes it will eventually take an edge (if your patient and skilled enough). But good luck keeping that edge for more than half a shave. The steel is steel, it polishes nicely and very very quickly. But its not going to hold an edge for very long.
However, won't shave worth a darn.
Same with aluminum.
Titanium might be worth exploring, but too expensive, and sheffield steel works plenty good for me.