Beskar

Mandalorian iron, also known by its Mando'a name of beskar, was an extremely durable iron ore whose only known source was the Outer Rim world of Mandalore and its moon, Concordia. The Mandalorian warrior culture that inhabited Mandalore mined their planet for beskar, using it in the creation of weapons, armor, and starships, occasionally even selling the rare and valuable metal on the galactic market. The introduction of certain additives during the smelting process served to increase the strength of the natural ore, and Mandalorian metalsmiths guarded the secrets of forging beskar from outsiders, passing along the techniques from one generation of metallurgists to the next, strictly within the Mandalorian community. A versatile metal, Mandalorian iron could be melded into multiple alloys and forged into various configurations.

Text and facts from the “Beskar/Legends” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.