Labyrinthite
An astonishingly complex eudialyte-group mineral — over 100 atomic sites and roughly 800 ions in its formula, which is how it got its name.
Intro adapted from Wikipedia (CC BY-SA).
Labyrinthite is an IMA-recognized mineral species in the silicate class, with the chemical formula (Na,K,Sr)₃₅Ca₁₂Fe₃Zr₆TiSi₅₁O₁₄₄(O,OH,H₂O)₉Cl₃.
It crystallizes in the hexagonal crystal system (space group R3). It is a member of the Eudialyte structural group.
Key properties: Mohs hardness 5–6; specific gravity 2.88; White streak; Vitreous luster; optically uniaxial.
IMA symbol Lby, IMA status: approved, named in 2002.
A late-stage pegmatitic mineral in an alkaline igneous complex.
It is found associated with K-feldspar, sodalite, alkali amphiboles, aegirine, pectolite, lamprophyllite, lomonosovite, villiaumite, lovozerite-group minerals.
Alludes to its very complex (labyrinthine) crystal structure.