Vlasovite and Gittinsite from the Kipawa Alkaline Complex, Quebec, Canada

Contributed by: Michael Crawford
Date: Sep 11th, 2025
Locality: Kipawa alkaline complex, Les Lacs-du-Témiscamingue, Témiscamingue RCM, Abitibi-Témiscamingue, Québec, Canada (See on Mindat)
Size: 8 x 14 cm

Description:
A specimen of vlasovite (Na2ZrSi4O11) and gittinsite (CaZrSi2O7) in a matrix of pink-red eudialyte (Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2) from the Kipawa Alkaline Complex, Les Lacs-du-Témiscamingue, Témiscamingue RCM, Abitibi-Témiscamingue, Québec, Canada. The specimen also contains a black mineral of the amphilbole group, albite and opal-AN. The Kipawa Complex is a regionally metamorphosed alkaline intrusive.

The gittinsite forms a reaction rim between the vlasovite and eudialyte matrix. This rim is best seen in the image of longwave fluorescence. The gittensite fluoresces white and the vlasovite and eudialyte are non-fluorescent under longwave UV illumination. In the white light image, the vlasovite is tan colored and the gittinsite is white.

The vlasovite and gittinsite both fluoresce under midwave UV illumination. The gittinsite fluoresces pale blue and the vlasovite fluoresces yellow. The midwave emission spectra show that both minerals also fluoresce in the ultraviolet when exposed to midwave light. The gittinsite peaks at 383 nm and the shoulder of this peak gives the bluish tint to the midwave fluorescence. The vlasovite ultraviolet peak is at 378 nm and its visible peak is at 528 nm.

The vlasovite fluoresces pale yellow under shortwave UV light. The emission spectrum of this fluorescence peaks at 518 nm and the peak is much broader than the midwave peak. The gittinsite is dim bluish gray under shortwave light. No information is currently available that describes potential activators for vlasovite or gittinsite fluorescence. Shortwave illumination causes albite to fluoresce red, and uranyl activated opal-AN to fluoresce green.