Murinite was a mineral which could be found on Rigel IV.

The Hill People of the Argus River region on Rigel IV used murinite for the handles of a kind of knives they produced; one such weapon was involved in a series of murders on Argelius II in 2267. (TOS: "Wolf in the Fold")

Minerals

Anorthosite • Antimonium • Bakrinium • Benamite • Beresium • Bernicium • Bilitrium • Boronite • Chrondite • Cormaline • Feldomite • Feldspar • Fortanium • Gallicite • Jakmanite • Jevonite • Kelbonite • Kemocite • Ladarium • Magnesite • Murinite • Neutronium • Nitrium • Noranium • Paralithium • Pergium • Regolith • Riddinite • Ryetalyn • Silithium • Styrolite • Talgonite • Topaline • Trellium • Tricyanate • Trimagnesite • Tritanium • Uridium • Vendarite • Zenite