Washington — Study of the Glaucophane Schists. 39 



subordinate amount, and quartz very abundant. This division 

 seems also to be in accordance with facts observed elsewhere. 



Some of these schists resemble closely the preceding, and 

 are rather bluish-gray, fine-grained, and highly schistose. The 

 specimen taken for analysis differs from all these, and is a very 

 striking rock, resembling (as far as can be told from the 

 description) some of the quartz glaucophane schists of Angel 

 Island, described by Ransome, to be mentioned later. 



It is a highly schistose, shining white rock, from the north- 

 west slope of Mt. Kappari. It is composed largely of quartz 

 and less white mica, forming a fine-grained groundmass, 

 through which are scattered blades of blue glaucophane, and 

 some garnets about one cm. in diameter. Accessory epidote 

 and apatite are also present in small amount. 



The analysis (No. IV, below), it will be seen, differs radically 

 from those of the other Syra rocks, being very acid, and with 

 all other oxides much lower, except K 2 0, which is quite high. 

 In a general way it resembles those of the acid glaucophane 

 schists of the Pacific coast. 



I. II. III. IV. 



Si0 2 46-39 46-76 58"26 79'43 



A1 2 U 3 17-34 22-65 16-2] 12-68 



Fe 2 O g 6-32 4-35 3'44 1-10 



FeO 4-62 1-74 4-63 1*86 



MgO.__ 4-93 393 4-99 0'48 



CaO „. 13-07 14-43 3*82 1*40 



NaO 2-95 2-36 5-36 1'61 



K 2 0-25 0-15 0-39 0*76 



H 2 OllO°+_- 1-48 2-87 0*98 1'03 



H 2 OllO°— .. 0-08 0-16 0-22 0'12 



C0 2 2-24 .-.- 0-00 



Ti0 2 0-85 not. det. 1'37 0-17 



MnO _ trace trace trace trace 



100-52 ' 99-40 99-67 100-64 



I. Epiclote-glaucophane schist. Kyperusa, Syra. Washington 

 anal. 

 II. Omphacite rock. Cafe Skarbeli, Hermoupolis, Syra. Wash- 

 ington anal. 



III. Mica-glaucophane schist. Cafe Skarbeli, Hermoupolis, 



Syra. Washington anal. 



IV. Quartz-glaucophane schist. KW. slope of Mt. Kappari, 



Syra. Washington anal. 



In connection, with the glaucophane schists of Syra, it will 

 be convenient to give the results of an analysis which I made 

 of the glaucophane of the island. The mineral was very 

 carefully separated by means of Thoulet's solution from a 



