334 KRAMM— SERPENTINES OF THE CENTRAL [June 6, 



small lenticular body of pyroxenite is found about one quarter mile 

 southeast of Coyote station. It is made up entirely of enstatite 

 which is unaltered, and an analysis of which by the author is here 

 given. 



Analyses. 



Pyroxenite- Enstatite- 



Serpeniinc. pen'dotite. pyroxenite. 



I. II. III. 



Per Cent. Per Cent. Per Cent. 



SiOo 37-71 42.76 56.98 



AI0O3 1.81 5-71 1-73 



Fe203"| „ 3-i6 404 



FeO J '^^ 3.30 4.18 



MgO 35.60 27.11 27.40 



CaO 10.03 3.26 



Na20 2.24 .59 



K2O .49 -35 



H.O 4.85 2.04 



CT2O3 — — .22 .09 



TiOi 09 .17 none 



85.68 100.04 100.66 



I. Serpentine of the Oakhill area by U. S. G. S. Analyst not stated. 



II. Pyroxenite-peridotite of Oakhill area. H. E. Kramm, analyst. 



III. Enstatite-pyroxenite from near Coyote. H. E. Kramm, analyst. 



South of the Oak-Hill area on the west side of Santa Clara 

 valley, opposite the Coyote area, and having an approximately paral- 

 lel trend with it, are several isolated areas of serpentine. The most 

 northern one terminates on the road leading from San Jose to the 

 New Almaden Quicksilver Mine. The most southern one is found 

 about two miles northwest of IMorganhill. A small area is also 

 found near New Almaden. 



The serpentine in general resembles that of the Coyote area, but 

 shows a somewhat greater degree of decomposition. 



About three miles southwest of Redwood in San Mateo County 

 is a considerable area of serpentine. Its maximum width is some- 

 what over a mile, its linear extent four miles with a trend north- 

 west-southeast. 



Smaller areas are also found at the following places: one east of 

 Searsville Lake about six miles west of Palo Alto, several south of 



