What is the hardest metal known to man

So im not trying to find diamonds here. i just want to know what the hardest metal is.
I wish to have my own custom guitar (i know ill probably have to become pretty well known for that but im working at it :) im pretty good right now, this all being becides the point.
And with this custom guitar i want it to be made of the hardest metal ever, so i could smash it and it would have no damage at all, not even rattle.
The reason being for this is so i can have a guitar last me my entire life no matter how its treated, or until it rusts.

Titanium is certainly one of the hardest metals known to man BUT it is notoriously difficult to work with AND it is rather expensive, put it this way, if you built a guitar out of titanium , it'd be worth more than most peoples homes.

titanium is the hardest metal to man and it is expensive and diamond is not a metal it's a stone. you can get titanium guitar but you would need it customized.

Heavy metal, bro. ;P