CONTENTS VII 



TABLES 



Page 

 TABLE 1. Analyses of graywacke from the Franciscan group, with average of 30 graywacke and 40 granodiorite analyses 



for comparison 17 



2. Analysis of siltstone of the Franciscan group, with analyses of graywacke and a composite of 78 shales for com- 



parison 



3. Analyses of alta and siltstone from the Franciscan group, New Almaden district, Santa Clara County 20 



4. Pebbles of a conglomerate of the Franciscan group exposed on Cemetery Hill, New Almaden district, Santa Clara. . 20 



5. Analyses of Calera-type limestone from near Permanente Creek, Santa Cruz quadrangle 24 



6. Bulk analyses of Calera-type limestone from quarries of the Permanente Cement Co. near Permanente Creek, 



Santa Cruz quadrangle 



7. Analyses of cherts and shales of the Franciscan group 



8. Analyses of greenstones of the Franciscan group, with composite analyses of diabase and spilite for comparison.. 



9. Analyses of serpentine rocks from the New Almaden district and from elsewhere in the California Coast Ranges, 



together with a composite of 24 serpentines from other regions for comparison 



10. Partial analyses of serpentine rocks from the New Almaden district and adjacent area 54 



11. Analyses of rocks from the New Almaden mine showing change from serpentine to cinnabar-bearing silica-carbonate 



rock 



12. Analyses of rocks from the New Almaden mine showing change from serpentine to silica-carbonate rock 63 



13. Average chemical composition of serpentine and silica-carbonate rock from the New Almaden mine, together 



with calculations to show chemical changes involved in the formation of silica-carbonate rock from serpentine. _ 63 



14. Pebbles from conglomerate in the Upper Cretaceous rocks of the Sierra Azul and the Franciscan group, Santa 



Clara County 65 



15. Composition and maximum indices of refraction of carbonates from the New Almaden district 100 



16. Approximate yield of quicksilver per linear foot of workings in some California quicksilver mines 107 



17. Annual production of the Guadalupe mine, Santa Clara County 163 



