Kozu and Washington — Augite from Stromboli. 469 



ences in composition, as shown by their analyses and as 

 expressed by the names applied to them, containing much 



the same 



augites, is 



rather striking. 







Table II. 



Analyses 



OF THE 



ROCKS CONTAINING THE 



AUGITES 







op Table I. 







SiO, 



50-83 



5105 



44-85 



50-41 



46-73 



A1A 



1666 



1509 



12-55 



12-27 



1005 



Fe 2 3 



1-52 



2-07 



3-33 



5-71 



3-53 



FeO 



6-64 



6-88 



5-30 



3-06 



8-20 



MgO 



6-08 



6-52 



10-27 



8-69 



9-68 



CaO 



10-99 



11-34 



8-32 



7-08 



13-22 



Na o 



2-66 



2-53 



4-77 



0-97 



1-81 



K„6 



205 



2-02 



0-72 



7-53 



3-76 



ELO + 



0-36 



015 



201 



1-80 



1-24 



ELO — 



• ■ > 



• • • 



0-95 



0-46 



... 



Ti0 2 



0-81 



0-83 



5-07 



1-47 



0-78 



P 2 5 



1-61 



1-44 



117 



0-46 



1-52 



MnO 



012 



0-13 



007 



015 



0-28 



NiO 



n.d. 



n. d. 



0-23 



004 



n. d. 



100-33 



*100-12 



99-60 



tl00-42 $100-97 



* Includes ZrO, = none, S0 3 = 006, Cr,0 3 =005. 



f Includes V 2 3 = 003, BaO == 0-23, SrO = 006. % Includes CI = 018. 



A. Basalt scoria; August, 1914, Stromboli, H. S. Washington analyst. 

 F. A. Perret, this Journal, 42, p. 451, 1916. 



B. Basalt scoria; November, 1915, Stromboli, H. S. Washington analyst. 

 F. A. Perret, ibid. 



C. Analcite basalt; Scano, Monte Ferru, Sardinia, H. S. Washington 

 analyst, Jour. Geol., 22, p. 748, 1914. 



D. Syenitic lamprophyre; Two Buttes, Colorado, W. F. Hillebrand 

 analyst. W. Cross, Jour. Geol., 14, p. 163, 1906. 



E. Shonkiuite; Square Butte, Montana, L. V. Pirsson analyst. Weed 

 and Pirsson, Bull. Geol. Soc. Am., 6, p. 414, 1895. 



Tohoku University, Sendai, Japan, and 



Carnegie Geophysical Laboratory, Washington, D. C. 



