Class : Silicates
    Subclass : Nesosilicate
    Crystal system : Monoclinic
    Chemistry : BeAlSiO₄(OH)
    Rarity : Rare

This rare aluminum beryllium nesosilicate is found in some pegmatites and chloritoschists (sometimes in alpine fissures as a decomposition product of beryl). Unalterable, it is sometimes concentrated in alluvium. Its name comes from the Greek eu (good) and klasis (breaking), alluding to its excellent cleavage. The euclase is always cristallsié in prime elongated and striated longitudinally, often tabular and rich in faces. It is transparent to translucent, colorless, yellowish, pale blue-green to blue, and has a high hardness (7.5). It is a mineral occasionally cut as a gem and sought after by collectors.

This mineral is not present in the French underground.

No twinned crystals for this species.

No fake recorded for this species.