104 ANALYSES OF ROCKS ‘AND MINERALS, 1880-1908. 
G. Analcite basalt, from the Basin. Monchiquose. Contains phenocrysts of augite, 
olivine, and analcite. Also magnetite, with subordinate amounts of alkali feldspars, 
biotite, and apatite. P. R. C. 1322. 
H. Portion of the analcite basalt soluble in hydrochloric acid. 
I. Augite separated from G. 
J. Analcite separated from G. After deduction of 4.22 per cent of substance insolu- 
ble in boiling dilute hydrochloric acid, and later removal of liberated silica with 
weak potash solution. Sixty-two one-hundredths per cent of the water goes off 
over sulphuric acid. A trace of lithia was found. 
The analcite basalt and its fractions are described by Cross in Jour. Geology, vol. 5, 
p. 684. 
G ui. I J 
TO uate er yc pcg dace rete ua ean a A raed 45.59 | 44.44] 49.26] 51.24 
Ne Os crevasse ciao cee aisya detec vin ercinraerstevasiers onsen sie anata birenctacser areas 12.98 }@20.11] 6.01] 24.00 
peers ee etree sects eee cannes geese that idl 4.97 \ 7.50 | 3.31 1.20 
BEG Oe 2 seep Saas rage ic nel etch i ott at ee ard 4.70 4.23 
MBO assis ajeg astaiernete seeaeetirgy ataleduaeteenet Bede ation MEeMioceenee 8.36 | 5.81 | 12.40 33 
CaO 11.09 3.94] 21.79 1.62 
Nae 4.53 | 8.17 -79| 11.61 
K 1.04} 1.13 41 1.25 
-51 undet. 
2 
H20 
H20 above 100°. 
TiO: 
2 Includes P20; and possible ZrO2 and TiO. 
3. SILVER CLIFF AND ROSITA. 
Rocks described by Cross, mostly in 17th Ann., pt. 2, p. 263. Also, partly in Proc. 
Colorado Sci. Soc., vol. 2, p. 228. Analyses, with one exception, by L. G. Eakins. 
Those with record numbers attached were made in the Washington laboratory; all 
others in the laboratory at Denver. 
A. Peridotite, Cottonwood Gulch. Custerose. Contains hornblende, biotite, 
hypersthene, olivine, a little plagioclase, apatite, pyrrhotite, and sillimanite (?). 
P. R. C. 519. 
