Ununhexium
Atomic Symbol Uuh
Atomic Number 116
Atomic Weight 289.
presumably a solid at 298 K
Color unknown, but probably metallic and silvery white or grey in appearance

Ununhexium is a synthetic element that is not present in the environment. Isolation of an observable quantity of ununhexium has never been achieved, and thus ununhexium has no known uses. The reactivity of ununhexium is unknown, but is assumed to be similar to polonium and tellurium.

Ununhexium was first seen in 1999, as newly created atoms of ununoctium decomposed:
Ununoctium(293) = Ununhexium(289) + Helium(4)

No name has yet been suggested for element 116, which is therefore called ununhexium, from the Latin roots un for one and hex for six, under a convention for neutral temporary names proposed by the International Union of Pure and Applied Chemistry (IUPAC) in 1980.

UPDATE
according to
http://enews.lbl.gov/Science-Articles/Archive/118-retraction.html Element 118 was never really synthsized. I'm pretty sure this means we've never seen 116 either.

                 polonium
                     ^
ununpentium <-- ununhexium --> ununseptium