Discovered 1819 in Greenland, this gemstone is usually found in massive forms in host rocks. Eudialyte is an extremely rare and complex mineral that occurs in red-violets, pinks, blues, yellows and browns. Well-formed crystals are rare, and opaque material is often fashioned in cabochons.
General Information
Common Name
Eudialyte
Species
Eudialyte
Transparency
Translucent - Opaque
Dispersion
Strength: None
Refractive Index
1.591-1.633
Birefringence
0.003-0.01
Optic Character
Uniaxial
Optic Sign
Positive
Polariscope Reaction
Aggregate (AGG), Doubly Refractive (DR)
Fluorescence
SWUV: Inert
LWUV: Inert
LWUV: Inert
Pleochroism
Unobservable
Hardness
5-5.5
Streak
White To Pale Pink
Specific Gravity
2.740-3.000
Toughness
Poor
Luster
Vitreous, Dull
Stability
Poor
Fracture
Uneven
Cleavage
Perfect, in one direction, Poor, in one direction
Chemical Formula
Na4(Ca,Ce)2(Fe,Mn,Y)ZrSi8O22(OH,Cl)2
Crystal System
Trigonal
Chemistry Classification
Silicate
Eudialyte Colors
-
Blue
-
Pink
-
Multi-color
-
Red
-
Orange
-
Yellow
-
Brown
-
Purple
Countries of Origin
Russian Federation; Unknown