Yay, a chemistry topic. I would have to say Platinum. Its very rare and also quite shiny and beautiful. Much less conspicuous than other metals and yet, it can surpass even gold in its worth. It's also a great catalyst and about as pure a metal as you can get, with some of the lowest reactivity of all the metals on the table. Plus, I like how the name sounds classy. It doesn't have quite the hubbub and the recognition of gold, but its just as worthy, and I love it for that.