564 



S. KOZU 



with very fine crystals of augite, is observed along the cracks in 

 the quartz. Glass inclusions with gas bubbles are present in 

 bipyramidal shapes, and ruptures starting from the four corners 

 of the rhombic sections are well marked in thin sections of the 

 mineral nearly parallel to the optic axis, as shown in Figs. 3 and 4. 



Fig. 3 



Fig. 4 



Chemical characters. — The analysis of the rock, shown in column 

 A in the following table, was made by T. Ono in the laboratory 

 of the Imperial Geological Survey of Japan. The analysis of the 

 quartz-basalt from the north base of Lassen peak, described by 

 Diller, is given in column B. 



Si0 2 . 



A1 2 3 - 



Fe 2 3 



FeO. 



MgO. 



CaO. 



is. 12 



2 . 46 



6.97 



313 



7 14 



Na 2 2.02 



K 2 1 . 



H 2 o. 



Ti0 2 1 



PA 



MnO o 



BaO 



Cr A •' • • 



SrO 



LiO 



16.51 



8.10 

 4. 26 

 2.68 

 452 



8. i S 



3 23 

 115 

 0.69 



0.48 

 o. 14 

 0.11 

 0.04 



tr. 

 0.04 



tr. 



A. Quartz-basalt (lava). 



B. Quartz-basalt (lava). 



* Loss on ignition. 



99.22 IOO.IO 



Kasa-yama, prov. Nagato. 



North base of Lassen Peak, California. 



