 Rhenium has one stable isotope, rhenium-185, which nevertheless occurs in minority abundance, a situation found only in two other elements (indium and tellurium).Naturally occurring rhenium is only 37.4% 185Re, and 62.6% 187Re, which is unstable but has a very long half-life (≈1010 years).This lifetime can be greatly affected by the charge state of rhenium atom.