These aggregates can appear glassy, dull or even fiberous. The aggregate nodules can often accompany many fine and rare minerals such as apophyllite , okenite and many of the zeolites .
Color is white or colorless.
Also green or brown. Luster is vitreous to dull. Transparency crystals are transparent to translucent. Nodules or concretions are lamellar to fiberous. Cleavage is perfect in one direction.