Chemical composition: Na4(Ca,Ce)2(Fe+2,Mn+2,Y)ZrSi8O22(OH,CI)2
Colors: Yellowish brown to brownish red, red or pink.
Hardness: 5 to 5.5
Formation: Rhombohedral, tabular or prismatic crystals
Principal Sources: Russia; Canada
Special Notes: Eudialyte, whose name derives from the Greek phrase eu dialytos, meaning "well decomposable", is a somewhat rare, red silicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites. Its name alludes to its ready solubility in acid. Eudialyte is used as a minor ore of zirconium. Another use of eudialyte is as a minor gemstone, but this use is limited by its rarity.