306 
DESCRIPTIVE MINERALOGY. 
248. 
. 249. 
Fig. 247. 
r 
r 
M 
m' 
~~s 
/ 
M 
M 
AT M 
St. Lawrence County. Hornblende, in almost all its varieties, occurs in several parts 
of this county. Crystals of va 
rious shades of green are found 
in the vicinity of the village of 
G ouverneur, where they are 
often associated with apatite, 
pyroxene, tourmaline, feldspar 
and quartz. These crystals are 
sometimes two or three inches 
in diameter, but are usually 
short. The forms observed here 
are similar to those represented in Fig. 244 ; also Figs. 247, 248 and 249. 
Fine crystals have also been obtained in the town of Dekalb. They often have a diameter 
of two or three inches, but the prisms are short. A very perfect one, in the possession of 
Dr. Emmons, had the form of Fig. 230. Crystals similar to 234, but with the prisms very 
short, have also been found in this county. 
In the town of Rossie, about two miles north of the village of Oxbow, there is a rock on 
Fig. 250. the road-side, from which beautiful and perfect crystals of the variety 
pargasite have been obtained. They are of a fine green colour, translu 
cent, and have a high lustre. The associates are pyroxene, feldspar, 
sphene and apatite. The usual form is the six-sided prism with two 
terminal planes (Fig. 243); often there are found compound crystals, as 
represented in Fig. 250. This is one of the most interesting localities in 
the county. 
Resplendent hornblende, in large crystals, associated with other mine¬ 
rals, has been found near the bridge at the village of Potsdam; and a 
white variety, in crystals terminated at each end, sometimes an inch long 
by three-eighths of an inch in diameter, has been found near Russel.* 
On the banks of Yellow lake, in the same town, tremolite of a bluish white colour, and 
resembling tabular spar, occurs in the white limestone ; and the same variety has been found 
in Gouverneur, and also at Richville and Dekalb, where it is associated with soft pyroxene, 
brown tourmaline, etc. At the latter locality, it is white and grey, fibrous and bladed. 
Tremolite has also been obtained in other parts of the county, and is indeed one of the 
most common and abundant minerals of the white limestone formation. The asbestus variety 
occurs in thin veins in the serpentine near the village of Gouverneur, and also near Little 
York. In the town of Dekalb, it is found in gneiss, and in perpendicular fibres of from a 
quarter to three quarters of an inch, passing through magnetic iron ore. The latter resembles 
the byssolite. With this exception, the asbestus heretofore obtained in this county does not 
possess much interest. 
* Finch. American Journal of Science. XIX. 220. 
