Lorenzenite is a rare sodium titanium silicate mineral with the formula Na2Ti2Si2O9 It is an orthorhombic mineral, variously found as colorless, grey, pinkish, or brown crystals.

It was first identified in 1897 in rock samples from Narsarsuk, Greenland.

It occurs in nepheline syenites and pegmatites in association with aegirine, nepheline, microcline, arfvedsonite, elpidite, loparite, eudialyte, astrophyllite, mangan-neptunite, lavenite, rinkite, apatite, titanite and ilmenite.

[2] It was named in honor of Danish mineralogist Johannes Theodor Lorenzen (1855–1884).

[3] This article about a specific silicate mineral is a stub.