28o The American Geologist. November, i899 
^ Ontario 
2. Syenyte-pegmatite ] India 
( Russia 
3. Nepheline syenyte \ Ontario, only. 
! Ontario 
India 
Russia 
The mineral also occurs in another igneous rock in India, 
viz.: granite. This mode of occurrence has not been observed 
in Ontario, although the corundum-bearing syenyte appears to 
shade off into granite in some cases. 
Morozewicz proposes the naine kystchtymit for the corun- 
dum-anorthite rock of Russia. Instead of introducing a new 
name, it would seem better to use the term anorthosyte, which 
has long been used by Canadian geologists and others for 
igneous rock whose characteristic constituent is a plagioclase. 
A specimen of the corundum-bearing anorthosyte from the 
mass in the township of South Sherbrooke was analyzed for 
me by Mr. Wm. Lawson, B. A. Sc. His results are given in 
the following table, together with three analyses of rocks of 
similar chemical composition from other districts. The speci- 
men selected for examination by Mr. Lawson was free from 
corundum. 
I 
II 
III 
IV, 
Seine River 
Russia 
South Sherbrooke 
Ottawa 
SiO, 
46.24 
46.54 
47-32 
47-40 
Al.Og 
29.85 
3073 
30-36 
30.45 
Fe^Og 
1.30 
3-23 
1-35 
0.80 
FeO 
2.12 
1. 18 
1-55 
MnO 
trace 
CaO 
16.24 
1545 
15-45 
14.24 
MgO 
2.41 
1-35 
2.44 
0.87 
NagO 
1.98 
1.36 
1.88 
2.82 
KaO 
0.18 
0.52 
0.66 
0.38 
CO2 
1.03 
0.58 
2.00 
HgO 
0.04 
O.IO 
volatile 
Total 
101.35 
100.40 
ioi.6g 
98.96 
Sp. gravity 2.85 
2-73 
2.73 
I. Seine River.Western Ontario. Described by A. P. Coleman in 
the Journal of Geology of Chicago, Dec-Jan., 1896. Seine River lies 
about 800 miles to the northwest of South Sherbrooke. 
