22 
museum bulletin NO. 4. 
a total of 75 per cent by volume for the rock. The specific 
gravity of the analcite was taken at 2-25, and that of the rock 
determined to be 2 ■ 388. A simple calculation gives 7 1 per cent 
as the proportion of analcite by weight recognizable in the rock. 
This amount of primary analcite is very exceptional, and 
marks the rock as an extraordinary type. Percentages of anal- 
cite up to 40 are not uncommon in analcite-tinguaites and mem- 
bers of the monchiquite family, and Coleman has described 
a dyke of heronite from Heron bay, Ontario, which contains 
47 per cent analcite. 1 
Up to the present, so far as the writer is aware, this was 
the highest percentage of primary analcite found in an igneous 
rock. 
Using the 71 per cent of analcite as a guide, the mineral 
composition of the rock was calculated from the analysis, with 
the following result: — 
Analcite 71 percent 
Jigirite-augite 14 “ 
Nephelite 5 “ 
Sanidine 4 “ 
Melanite 1 u 
Titanite 0*5 “ 
Hematite 1 “ 
Calcite (secondary) 2 “ 
Water (free) 1-5 “ 
100 
These values are not to be regarded as exact; there is 
probably, for instance, more analcite than given above, as that 
represents only the visible, crystallized mineral. There is 
also some free secondary silica, which was left out of consid- 
eration and may amount to 1 or 2 per cent. 
The chemical analysis of the blairmorite, as well as of the 
analcite phenocrysts are given below. For these analyses the 
writer is indebted to Mr. M. F. Connor, of the Department of 
Mines, Canada. The analysis of the blairmorite was made 
Coleman, A. P., Journal Geology, vol. 7, 1899, pp, 431-436. 
