IGNEOUS AND CRYSTALLINE ROCKS. 153 
G. Diorite, north fork of Mokelumne River. Amadorose. Contains quartz, feldspar, 
biotite, sphene, epidote, and secondary chlorite. P.R.C. 771. 
H. Diorite, north fork of Mokelumne River. Andose. Contains plagioclase, 
quartz, hornblende, biotite, apatite, iron ore, epidote, and chlorite. P. R. C. 772. 
I. Plagioclase gneiss, north fork of Mokelumne River. Hessose-andose. Contains 
plagioclase, hornblende, biotite, and apatite. P.R.C. 768. 
J. Plagioclase gneiss, north fork of Mokelumne River. Bandose. Contains plagio- 
clase, hornblende, brown mica, apatite, epidote, and grains of iron ore. P. R. C. 767. 
G H, I. J 
SO So dicteccienciseareratctdigtinnstens sed nidia sree aie. givisle esis ee taurus aR Sem ERS 69.66 | 55.86 | 52.21 46. 63 
ANIO 9. on steu ce sew crs en cmee eee seals oe sis be wie alate peretrendiaie era ermorsereicinicions 17.57 | 19.30] 18.79 19. 47 
BOs scone. centscase ve vvdeaeis isemsaa ree reese seeieewwieeseeeideeeses ays 21 91 2.71 3. 26 
POO oy canes tetinteds oe ace muiein Boils Bewehad geet ie EERE CRESS Says 1.04 4.78 5.30 6. 63 
MO a sisscs,ceses arn csesedvicie ian ersiesnis ie tie etoile eaieiiarnas Sex sie ae ee SR SRC REE 58 2.94 5.11 5.37 
CAO ied or cept areas Sac eee Steeaea ieee arnis au aaeeeecineeileeREearEe 4.54 7.31 8.01 9.15 
INDO sci smer an ienntinka sora cat me mamsm ee ani wpablemiecameiais tion seen 4.91 3.52 3.31 3.19 
KO eoeieces shar anaes a rocaciee Sate eaamacEeeeeadeeenenscaoeeeeced adae etek 71 1.52 1.60 1.55 
Fs: at W108 ooo cectcicrais cd ranaalncumetiun sstecins scuwzarkmamia nese tes aeratis -05 19 -12 -10 
sO BbOVe 110%: 2x vases cesacigh vista cre ctesd aslo gatelsieial pdiamiiesinmainaee aes Bee - 50 1.23 1.35 1.61 
PIO 9 ras sen eseer neon = seaee augers mee odeise ce macnn nhclsetescaisiemts +21 1.20 1.16 1.82 
20,-- gewntd Sine gael piowenre! 03 -38 . 36 - 66 
VO oasis ch cic cio rgeernde paenca Gag hac aE s Skee ceeeeeeretarades se teeweced| seladzcieg le ovaude!s 02 
INT OES oS rapes 2yanSsoeciin Gerssethevs desscieeieis wieid na teactsl tie ede Goes Cina G Bie MeL RS MEM NS ee none} trace | trace 02 
MUO oss Bot oeae ei Si Raid ao namend eld spins epiemetpeweinaeemacemames os trace 16 06 21 
BSE) isa chs sys capers eee devsests aga emtaymyai gE Sea te Goce es ae scence wis wasted prepentaneletenes -05 OE | setsesrnis 06 
BAO sere cieicrncraiseiekekictse i Demeianis Ben Pahmaes Ae ESOS aa ae Deeena nee oeteiees - 03 13 08 14 
Dba Q occa sic ateee aszyoanciarasciore secs ness be RnceReE ea eTieeee SeRERMMERE REROTSRS ENS none | trace | trace trace 
CO bas encucemearsexmceen tote Tue Sei ecinne s deta rchnsh aatepinaaweeR TSS none | none | none none 
OR 3 ieserced nese ea dvarcnes Beta Ne Serle ee ee yauaS ne bate erie BaieimveNtetanse trace? 39 06 19 
100.09 | 99.86 | 100.23 | 100.08 
K. Wollastonite gneiss, north fork of Mokelumne River. Mainly wollastonite, but 
garnet, quartz, and sphene are also present. P. R. C. 766. 
L. Melaphyre tuff, altered basalt, west of Jackson. Contains augite and plagioclase, 
with secondary quartz, chlorite, and chrysotile. Originally glassy in part, “but 
devitrified. See 14th Ann. P. R. C. 722. 
M. Reddish-brown mica separated from pyroxenic gneiss, north fork of Mokelumne 
River, about 1 kilometer above mouth of Bear River. Described by Turner in Am. 
Jour. Sci., 4th ser., vol. 7, p. 294. Analysis by William Valentine, record No. 1736. 
