168 ANALYSES OF ROCKS AND MINERALS, 1880-1908. 
3. CRATER LAKE. 
Rocks collected by J. 8. Diller. All except the last one in the series are described 
by H. B. Patton in P. P.3. Analyses A to N, inclusive, by H. N. Stokes, record Nos. 
1671, 1953. 
A. Vitrophyric rhyolite, south edge of Llao Rock flow. Lassenose. Contains plagio- 
clase, hypersthene, hornblende, and apatite in a glassy groundmass crowded with 
augite microlites. P.R.C. 1814. 
B. Streaked rhyolite, near ‘‘Wine Glass” Grotto Cove. Lassenose. Contains plagio- 
clase, hypersthene, hornblende, and magnetite, with biack glass. A few small inclu- 
sions of basalt and hypersthene andesite. P. R. C. 1316. : 
C. Rhyolite, small dike immediately below Llao Rock. Lassenose. Contains 
plagioclase, hornblende, hypersthene, and magnetite, in a glassy groundmass crowded 
with microlites of feldspar and augite. P. R. C. 1317. 
D. Rhyolite, water’s edge, head of Cleetwood Cove. Lassenose. Contains plagio- 
clase, hypersthene, brown hornblende, and magnetite, in a feldspathic groundmass 
of trachytic type. P.R.C. 1315. 
E. Hypersthene-augite andesite, large dike transsecting the northwestern portion 
of the crater rim. Tonalose. Contains plagioclase, hypersthene, augite, and magnet- 
ite in a groundmass having a moderate amount of glass. P. R. C. 1313. 
F. Hypersthene-augite andesite, west edge of Wizard Island. Tonalose. Same 
mineralsasE. P. R. C. 1309. 
A B Cc D. E F 
SiOg: wa see ansneesasceaducatd sof otemditaadeatnas ae: 70.77 | 68.17] 71.78) 70.10} 60.09} 59.39 
AUS OW 6s Senanarcinerane mee selene nate te Race ucimaalenite 14.83 | 15.60] 14.53} 15.18] 17.85 18. 45 
O98 os scorer srarrsuts nd setaneeemeeuisenastinrreatoresacesems 1.35 2.31 1.28 1.78 2. 03 1.79 
BOO i 3 perdaisanyavacdbisitsice.e yemmenuicintienesciermamaaete ss 1. 25 94 1.02 1.09 8. 45 3.90 
Mg Olecuaceeauhe 64 1.02 - 48 74 3.50 3.13 
CaO.. 2.12 2.76 1.59 2.27 6. 28 6,29 
Na2O 5.07 5.15 5. 08 5.15 4.17 4,29 
Kk.0. 2. 68 2. 46 2. 84 2. 58 1.31 1,29 
HO at 110°. . 2 07 09 - 06 10 <d2 -10 
HaO above 108s 2.0 cacncae scewancndemeacscS-escshe nes 83 = 45 22 +19 26 ~42 
DO) gerarceacdeciacovcra isis Oise adiamderarsieene see emecigenicbead Ene - 38 54 41 - 48 54 41 
P20s. 13 13 .10 -13 +23 w22 
ZrO2. 05 | none 04 -04]) none none 
NiO.. none} none | none| none none 
sro. 02 03 03 - 03 05 
BaO 08 06 08 - 08 05 05 
DisQ ane seceevig seein coe ceisetammurs vein veal cemineteeteie ne trace | trace | trace | trace | trace trace 
Las gyareensqoaeieeri es weememalsee eet ct ee eagenwesilestis vee 11 | trace | trace -03 | trace trace 
99.88 | 99.71 | 99.63 | 99.97 | 99.98 99.77 
Traces of manganese inall. Fluorine not sought for. No CO2, S, SOs, or CreO3 in any. 
G. Hypersthene-augite andesite, crater rim, just south of ‘‘The Watchman.” Ton- 
alose. Same mineralsasF. P. R. C. 1310. 
H. Hypersthene-augite andesite, Palisades, under Round Top, northeast portion 
of the rim. Tonalose. Contains plagioclase, hypersthene, augite, and magnetite. 
P.R. C. 1312. 
I. Hypersthene-augite andesite, lake level, under Llao Rock. Tonalose. Same 
mineralsasH. P.R.C. 1311. 
J. Basalt, base of Red Cone. Andose. Contains plagioclase, augite, olivine, and 
magnetite, with some glass base. P. R. C. 1321. 
