Chemical Formula: Na2Be2Si6O15 · H2O
Locality: Island of Aro, Langesundfiord, Norway.
Name Origin: From the Greek epi, “near” and didymos, “twin”, for its dimorphous relationship with eudidymite
Physical Properties
Cleavage: {001} Perfect, {010} Perfect
Color: Colorless, White, Gray, Yellow, Blue.
Density: 2.55
Diaphaneity: Transparent to translucent
Fracture: Brittle – Generally displayed by glasses and most non-metallic minerals.
Hardness: 5.5 – Knife Blade
Luster: Vitreous (Glassy)
Streak: white
Photos :
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