Sennum

Sennum is a fictional mineral described in science fiction as a dense metallic ore with high energy density and stability under extreme conditions. It is often invoked as a future energy carrier or material for propulsion.

In-world descriptions vary; common elements include metallic luster, ductility, and an ability to release energy when processed in specialized reactors. Sennum is typically presented as relatively scarce, with refining requiring complex metallurgy and precise heat treatment. Its oxide is described as protective, reducing corrosion in certain environments.

Occurrence and extraction: Sennum is said to form in deep crustal settings, often alongside rare earth minerals. Mining is depicted as hazardous, involving deep underground operations, high pressures, and careful waste handling.

Uses and impact: In-fiction, sennum serves as a high-density energy source for reactors, batteries, and starship propulsion, sometimes as a superconductive material. Its scarcity and geopolitical distribution drive trade networks and conflicts in narratives.

Etymology and cultural use: The name sennum appears in multiple works and is sometimes attributed to an ancient language within those worlds. The term has entered game and novels lexicons as a generic stand-in for advanced mineral resources.