60 ANALYSES OF ROCKS AND MINERALS, 1880-1908. 
oO zB Q. R. 
Oa excaryeg lack Seat asaeind ee cattt oerete Sis ls ym: 210 seas Miao a gs Oe MAO eAoRG eee 55.14 | 57.46 08 ‘42.95 
IANS OF races sre reeniare Siig mara mao Weems re RieseeH EMU aReE Rete esamer sas 18.98 | 18.41 | 18.38 12. 44 
BG esacAw a ouncseancmdows caraaseemenaied male un esialnenaanaiacsaneas 2. 2. 40 10. 16 
BO Os erscajserctane sia neisie aeeaiontons acini eenmeaaaie avnre reacties seemyecanes 1.62 1, 28 1.42 5.18 
MBO ieseeeecpasarecc rc ays verge ery iynalate telat diaiatecctaarecmareraniee eee SEER Ries ease 32 | none 96 5. 82 
CIO oc: jo aia ee VERaraeawan Sexe as peer esned mia aceracesine HeeREREE 3.96 4,02 3. 85 13.11 
IN AGO} soiacescroiecad me aenictmmetaain eee aR Ee ESSER EINER Ce aes etocincee aaeReE 5.38 9. 23 6. 22 2.10 
Wed Opa. 5,0 Prevetesie fsa a aieeeacas ntaicinia einai melee EER Oe aN ERR E Sea 6.64 4.93 5.11 2.29 
TsO tat MOD acc eiseenceicec Sis ao gsaiaiold aosscasesetiarniatsio Sass ee SR SE REE - 63 -45 37 91 
HO above Ss cee cecra iste as de daceealdcataciose iil cess ae ReER EES 3.70 1.12 1.55 1.98 
NO Sst. cis seems ceinayeisee ane se eae ee eee wind ae Motors lad Desi aeeeetini - 50 ~42 58 1.34 
BP 3 Oi pcikc ens cvsencdln eee ara arctcyoteistesianre cele Cai aR ae Hae Seca bid eaieeine eI 17 ell 21 1.37 
1G Og ence seaccechinte ween cinsn a ocestonemaaeb eet eI ane teReECaaw reer ecneeieses 10 50 -07 15 
sentedSuns ict eis/e ae ee nS ata Sct pierre oer SER eee aR se Pee trace .23 | trace 07 
ies 2 ciency aie: ial cas ats Err ei aig nara tia eel dann Hialate claicta-datereuem eGR amelie 03 05 | none none 
MT O)io.cinc2,djcne ceeaiseenion aw gar SAE RSE RO EE Rees cee Ieee trace ll -10 
TB SIO): casa save ces ysctvecare cjaroreasyeiieais/e.cias as DSaRRe iets TE SENG SORE EEE BES Ip ee ees a ieee none | none none 
99.77 | 100.72 | 99.92} 100.16 
TSOSS AQ per ds eceueesuen cra sh neni KERR aeleeoa Osea ato oaGatemte cee R eR 0 OB epsssecscteeess 02 
99.76 | 100. 64 |........ 100. 14 
No COzin any of these rocks. 
YELLOWSTONE NATIONAL PARK AND THE ABSAROKA RANGE, 
1. ELECTRIC PEAK. 
Rocks described by Iddings in 12th Ann., p. 577. Also in Bull. Philos. Soc. Wash- 
ington, vol. 11, p. 206. For analyses O, P, see Mon. XXXII, pt. 2. 
A. Pyroxene-mica diorite. Tonalose. Contains augite, hypersthene, plagioclase, 
quartz, biotite, hornblende, magnetite, and apatite. Analysis by J. E. Whitfield, 
record No. 830. P.R.C. 94. 
B. Pyroxene-mica diorite. Andose. Same minerals as under A. Analysis by 
Whitfield, No. 921. 
C. Pyroxene-mica diorite. Tonalose. Like A and B. Analysis by W. H. Mel- 
ville, record No. 1231. 
D. Pyroxene porphyry. Andose. Contains augite, hypersthene, biotite, mag- 
netite, plagioclase, and quartz. Analysis by Whitfield, No. 830. 
E. Quartz-pyroxene-mica diorite. Tonalose. Contains biotite, hornblende, augite, 
hypersthene, magnetite, plagioclase, orthoclase, and quartz. Analysis by Melville, 
No. 1231. 
A B Cc. D E 
SiOe2 58.05 | 61.22 | 57.38 64. 07 
Al2O3 18.00 | 16.14] 16.86 15. 82 
2.49 3.01 2.49 3. 40 
FeO. 4. 56 2.58 5.17 1.44 
MgO 3.55 4.21 5.51 3. 39 
Ky 
T1908 6100? secccccscscacwcade teenies vase we emewiaacne nencaee 04 -10 
120 above id0*.2 y 23} ge] Sh wae) 
