Euclase \Eu"clase\n. [Gr. e'y^ well, easily + ? to break. Cf. F.
euclase, G. euklas. See named from its brittleness.] (Min.)
A brittle gem occurring in light green, transparent crystals,
affording a brilliant clinodiagonal cleavage. It is a
silicate of alumina and glucina.
[1913 Webster]