Atomic Properties of Re
- Atomic Number of Re
- 75
- Atomic Mass of Re
- 186.2100 u
- Electron Configuration
- [Xe] 4f14 5d5 6s2
- Electronegativity
- 1.90
- Block
- d-block
- Group
- 7
- Period
- 6
Ida Tacke, Walter Noddack, and Otto Berg identified rhenium in 1925 and named it for the Rhine River. It was the last naturally occurring element with a stable isotope to be discovered. Rhenium is highly dispersed and usually recovered as a byproduct of molybdenum and copper processing, so supply depends on other mining streams.
Most rhenium enters nickel-based superalloys for turbine blades and related hot-section components. Small additions improve high-temperature creep performance, helping engines operate under demanding stress and heat. The blade remains a complex cast alloy with coatings, cooling passages, and finite service life. Rhenium does not make failure unacceptable or impossible; inspection and maintenance remain part of the design.
Platinum-rhenium catalysts rearrange hydrocarbon structures in petroleum reforming, supporting high-octane gasoline and hydrogen production. Catalyst regeneration and rhenium recovery matter because the element is too scarce to treat as disposable. “You won’t find him in everyday tools” reflects concentration of use, not absence from the products of those processes.
Natural rhenium includes stable rhenium-185 and radioactive rhenium-187. The latter decays to osmium-187 with a half-life around 41 billion years, forming a rhenium-osmium clock used for ores, meteorites, and planetary history.
This Forger is precise across wildly different timescales. Seconds of turbine stress, years of catalyst service, and billions of years of isotope decay all depend on a metal recovered atom by atom from someone else's ore stream. Rarity makes recycling part of performance.