dualite music — Photo: Stritfaytır · CC BY-SA 4.0
Dualite
An extraordinarily complex member of the eudialyte group, its formula packed with interchangeable cations.
Intro adapted from Wikipedia (CC BY-SA).
Dualite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₃₀(Ca,Na,Ce,Sr)₁₂(Na,Mn,Fe,Ti)₆Zr₃Ti₃MnSi₅₁O₁₄₄(OH,H₂O,Cl)₉.
It crystallizes in the hexagonal crystal system (space group R3m). It is a member of the Eudialyte structural group.
Key properties: Mohs hardness 5; specific gravity 2.84; White streak; Vitreous luster; optically uniaxial.
IMA symbol Dua, IMA status: approved, named in 2005.
developed during the final stages of peralkaline pegmatite formation.
It is found associated with K-Na feldspar, nepheline, sodalite, cancrinite, aegirine, alkaline amphibole, eudialyte, lovozerite, lomonosovite, vuonnemite, lamprophyllite, sphalerite.
The name comes from Latin dualis (dual) alluding to the dual taxonomic membership of this mineral, at the same time zirconosilicate and titanosilicate.