Washington — Study of the Glaucophane Schists. 51 



I. 



Si0 2 49-68 



A1 2 3 13-60 



Fe 2 3 1-86 



FeO 8-61 



MgO 6-27 



CaO 10-97 



Na 2 3-09 



K 2 0-12 



H 2 OlOO° + ) 



H 2 100°- f d84 



Ti0 2 1-31 



PA 0-21 



MnO 0-04 



II. 



49-08 



14-68 



1-95 



963 



6-69 



10-09 



4-60 



0-20 



j 1-18 



( 0-28 



1-72 



0-23 



0-15 



99*60 100-48 



I. Zoisite-glaucophane schist. Sulphur Bank. Melville anal. 

 Becker, Mon. XIII U. S. G. S., p. 104, 1888. 

 II. " Pseudodiabase." Mt. St. Helena. Melville anal. Becker, 

 op. cit., p. 98. 



While we are still in California, there may be quoted, for 

 the sake of completeness, two analyses given by Eosenbusch. 

 The first (I) is of a specimen sent him by Palache, of a " Grun- 

 schiefer with glaucophane, further stage of altered tuff. Hills 

 north of Berkeley." This is calculated from two partial 

 analyses and an alkali determination.* It shows a composition 

 very low in Si0 2 and MgO, probably high in iron, and high in 

 CaO and JNa 2 0, differing materially from others only in the 

 lower Si0 2 . 



The secondf (II) is of the albite-crossite rock described by 

 Palache,^: and which Turner§ thinks may be a dike rock. 



SiO ... 



I. 

 .... 42-59 



II. 

 65-2 



Al O 



) 



( 15-8 



FeO 



I 31-00 



] 2-7 



FeO 



MgO 



CaO 



Na 2 



K 2 



5-10 



10-80 



4-16 



1-01 



( 2-4 

 2-4 



0-6 



10-8 



o-i 



H 2 0,C0 2 _._- 



5-34 





100-00 



100-0 



716. 



* Rosenbusch, Sitzungsber. Preuss. Akad., 1898, p. 



f Rosenbusch, op. cit, p. 712. 



X Palache, Bull. Dept. Geol. Univ. CaL, vol. i, p. 181, 1894. 



§ Turner, 17th Ann. Rep. U. S. G. S., i, p. 728, 1896. 



