Imperfect in one direction
Has perfect cleavage on {001} and good cleavage on {010}. Cleavages intersect at 90°.
CaCuAlSi 2O 6(OH) 3Michael OâDonoghue , Gems, Sixth Edition (2006)
KAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references