676 



ARRHENITJS 



[CHAP. 25 



/ 



$ 



50 /x 



Fig. 13. Authigenic celestobarite from Pacific pelagic sediment showing frequent elongated 

 prismatic habit and barrel-shaped growth form (B). Varying degree of corrosion by 

 aqueous solution at separation is shown by A-H. I and J were protected against 

 corrosion by use of excess sulfate ion at separation. 



