SECT. 3] 



PELAGIC SEDIMENTS 



699 



10 /x 



'^li.^ 



m 



Fig. 27. Twinned zeolites of the phillipsite (K+ Na+; Ca2+)-harmotome (Ba2+) series. The 

 crystals tjqDically display extensive intergrowth with other phases, primarily non- 

 tronite, which often form as much as one half the volume. 



