GEOLOGY OF THE LONG LAKE QUADRANGLE 503 



for all possible local use. Perhaps the best material of all is the red, 

 granitic syenite, the color of which is pleasing, and not susceptible 

 to the change which the green syenite experiences. The handsome 

 lodge and gate at Litchfield park are constructed of this material, 

 and a prettier red granite would be hard to find [pi. 17]. The ma- 

 terial was obtained- from boulders within the park, and close at 

 hand, but there is a plentiful supply exposed in places to the east. 

 In all respects except that of color much of the syenite is an equally 

 good building material, and its original greenish shade is a pleasing 

 color to many; but its rather rapid change to brownish tints on 

 exposure to the air is a drawback. It has been used for foundation 

 and other work at Tupper Lake to a considerable extent and for 

 durability and strength is unexcelled. The color change is the 

 only drawback to its use for more pretentious work. 



The anorthosite is also a strong, durable stone serving well for all 

 rough purposes. The coarser varieties have had considerable use 

 in the region in the construction of rustic mantels and chimneys, 

 and the stone is very handsome when so used. None of it possesses 

 the property of iridescence in a high degree but much of it has some- 

 what of the character, and this enhances its effectiveness for such use. 



Road metal. The best stone for roadmaking in the district is the 

 basic variety of the syenite. This has been considerably quarried 

 at Tupper lake and used locally upon the roads, and also been ex- 

 ported to some extent [pi. 18]. It is hard and tough and has ex- 

 cellent binding power, being equal to the best trap rock in these 

 qualities. The more feldspathic syenite makes nearly as good road 

 metal as the more basic variety. The more gabbroic anorthosite 

 would also make a good road rock, though it has not been used 

 locally because of the plentiful supply of the syenite. 



Some of the roads of the quadrangle have been surfaced with 

 sandy gravel dug from the moraine along the roadsides. Where 

 carefully selected it makes a very good road provided its usage is 

 not too hard. In many cases however it has not been well selected, 

 and where there is heavy teaming it does not prove very durable. 



PETROGRAPHY OF THE ROCKS 



While the general petrography of many of the rocks of the 

 quadrangle has been given by Kemp, Smyth and the writer in 

 their various reports to the State Geologist, the work is far from 

 being exhaustive, and some more exact work on certain rocks 

 seemed desirable. 



