Nonsense. Nickel-iron asteroids are called "metallic," because they're largely made out of, well, metal. Stony asteroids are called "carbonaceous" because they'

Nonsense. Nickel-iron asteroids are called "metallic," because they're largely made out of, well, metal. Stony asteroids are called "carbonaceous" because they've got a lot of carbon. They're very definitely not called "metal". And astronomers believe that the core of Jupiter is both hydrogen and metallic -- hydrogen compressed to the point where it acquires the property of a metal. So: there are many things that are neither hydrogen nor helium nor metal, and a few things which are both hydrogen and metal.