240 Whitney's Geology of California. 
furnished considerable of the metal, but vastly less than the 
New Almaden. These three mines lie on a ridge—the culmin- 
ating points of which are about 1,600 to 1,700 feet high,—lying 
east of the main mass of mountains. Traversing this ridge area 
series of limestones, which may be traced much farther in each 
direction. Serpentine in large quantities, and bitumen in small 
quantities, are associated with the cinnabar in all of its localities. 
Prospecting has been largely prosecuted in both directions with- 
out important results. 
mass of Tertiary is folded between this ridge containing the 
mines, and the main mountain range west. This is seen in lim- 
ited quantities back of Mine peak, and it occurs again much 
more largely to the northwest. Whether the larger masses of 
Tertiary, lying in front of the main chain both to the northwest 
and southeast, are continuous along a belt behind the Mine ridge, 
labor is needed before the details of structure can be known. | 
e mountains back of the Mine ridge of New "A ioaelete are 
peculiarly rough and forbidding; many points rise to above 
8,000 ft., and the region is denuded into deep and a 7° ra- 
tent is not known. oe n this rock near Santa Cruz sup- 
ply the — of the lime mt in the San ieaadees market. ~ 
en the summits and Santa Cruz on the south, large 
masses ‘of Tertiary occur, slightly disturbed near the bay, but 
much broken farther back, Five terraces near the coast indicate 
~ csi $9 pe . lee : 
where i in thid riage cate rye wei found i in small quantities, ea" 
— — the metamorphic portion, and we have heard it re peat i 
edly stated that it may be detected in certain of the sands i 
the city of San Francisco itself. 
for coal in workable snunition toll 
been carried on at various. times, and cechout ts, and 
poe” oa ol — far a 08 
