THE CROWSNEST VOLCANICS. 
25 
I. Analcite phenocrysts from blairmorite, variety A, 
Collector, J, D. MacKenzie, Analyst, M F. 
Connor. 
II. Analcite from tuff in railway cut west of Coleman, 
Alberta. Collector W. W. Leach, Analyst C. W. 
Knight, Canadian Record of Science, Vol. 9, 
1905, p. 271. 
III. Crofthead, Dana, System of Mineralogy, p. 597. 
IV. Secondary analcite, Wassons Bluff, N. S., U.S.G.S. 
Bull. 207, p. 8. 
V. Theoretic composition. 
The lime and carbondioxide in the analcite are due to slight 
replacements of calcite, and are virtually molecularly equivalent. 
The potassium may be from small inclusions of sanidine, the 
titanium from inclusions of titanite, and the magnesia from 
segirite-augite. The ferric iron is clearly due to hematite, 
and this causes the red colour of the mineral. 
The analysis by Knight, in column II, is almost identical 
with the one now published for the first time in column I. 
The properties of the analcite that have been determined 
may be briefly summarized here. The colour is flesh red, and 
the lustre slightly vhrecus; cleavage is fair in the hand specimen, 
and very well shown in thin section. The mineral is soluble in 
hydrochloric acid, and on evaporation gelatinous silica results. 
Before the blowpipe it fuses to a slightly opaque glass, and gives 
much water in the closed tube. By the immersion method, the 
index of refraction was found to be greater than 1*466 and less 
than 1*495, perhaps about 1*48. 
Blairmorite , Variety B. This rock is represented by a 
rather weathered sample (field specimen 21) which was picked 
up on a ledge of the volcanics, and probably is a portion of a 
fragment from the breccias. It consists of about 50 per cent 
pinkish buff analcite phenocrysts, in regular icositetrahedrons 
up to one-quarter of an inch in diameter, but mostly about one- 
tenth of an inch. These are embedded in a dull green aphanitic 
matrix containing occasional phenocrystic specks of dark green 
pyroxene and black garnet. 
