It consists of iron (Fe), ruthenium (Ru), osmium (Os) and hassium (Hs). To date, no other elements have been known to decay to hassium. Hassium has no stable or naturally occurring isotopes. Hassium has been observed as decay products of darmstadtium. Hassium is a chemical element with the symbol Hs and the atomic number 108. According to Mendeleev's nomenclature for unnamed and undiscovered elements, hassium should be known as "eka-osmium".