plebium

Plebium is a hypothetical chemical element proposed in speculative science and fiction. In this context, it is assigned the symbol Plb and atomic number 170. Plebium is described as a dense, corrosion-resistant metal with an exceptionally high melting point and significant nuclear binding energy, making it a candidate for extreme-temperature technologies in imagined settings.

The name plebium is derived from the fictional term plebs, reflecting its proposed prevalence on many rocky bodies in the setting. The symbol Plb is a conventional abbreviation used in the literature. In real-world science, there is no formal designation for plebium.

Properties: In theoretical models, plebium is a dense metallic element with a lattice similar to other late transition metals. It is described as having a high density (tens of grams per cubic centimeter), a melting point around 3300 K, and a boiling point above 5000 K. It is predicted to resist corrosion and to form stable oxides. All known isotopes are radioactive, with half-lives varying by neutron number; no stable isotopes are predicted.

Occurrence and production: Plebium does not occur naturally in the real world; in fictional contexts it is synthesized in specialized particle accelerators or fusion reactors. Initial experiments in the literature place production in orbital facilities in the mid-22nd century.

Applications and research status: In the fiction, plebium is proposed for ultra-high-temperature alloys, radiation shielding, and compact energy systems. Its production remains challenging, and short-lived isotopes hinder practical use. Researchers focus on theoretical chemistry and materials science to assess possible compounds and structures.

---