Sample containing two minerals, the soft green globules are prehnite, a calcium aluminium silicate hydroxide and the furry white aggregates being okenite, a hydrated calcium silicate hydroxide. are often found associated with zeolites and sometimes thought of as zeolites. The three however belong to different subclasses of the silicates, prehnite, okenite and zeolites being phyllosilicates, inosilicates and tectosilicates respectively. Actual sample width is 110 mm.