GRANITE. Of the crystalline siliceous rocks, granite I q.v.) is undoubtedly the best known and most deservedly popular as a building stone. ('ommercially, this term granite is ap plied to all igneous and metamorphic rocks I see IGNEOUS ROCKS; METAMORPHIC ROCKS) ; but still the use of true granites predominates. They, together with syenites, include the strong est of building-stones, ranging in crushing strength from 25,000 to 30,000 pounds per square inch or more. They are very resistant to frost action, and are vommonly permanent in color. Until comparatively fecent times, on account of its great hardness, granite was employed almost wholly for massive masonry, since it could be used there with a comparatively rough dress ing; but with modern improved stone-cutting and dressing machinery, it is now turned and carved into columns, pilasters, etc., and polished with the utmost perfectness. In all times, how ever, granite has been (me of the moat popular of building-stones. The red granite of Syene, was fashioned by the ancient Egyptians into obelisks, sarcophagi, and colossal statues, and employed by them in building their temples, pyramids, and palaces. The Egyptian granite was red in color. Modern granites range in color from nearly white to dark gray, and from a delicate pink to a deep red. The average weight of granite is about 100I_ pounds per cubic foot, and its crushing strength is from 5000 pounds to 20,000 pounds per square inch. Suit,able granite for building purposes is found tvidely distributed. Tiw Scotch granites are the coarse red from Peterhead and the gray from Aberdeen. It is of the latter stone that the city of Aberdeen is largely built. Scotch granite is quite largely imported to the United States for monumental work. Both gray and red granite are quarried in Canada, stone of one or both colors occurring in British Colum bia, near Victoria: in Quebec, in many localities around the lakes at the heads of the Saint Fran cis and Alegantic rivers; in Ontario, near King ston; in New Brunswick, near Saint George; and in Nova. Scotia, near Shelburne. The prin cipal English granite is perhaps that from West moreland County.
In the United States, granite is quarried in practically every State bordering on the Appala chian Mountain Range, and in California, Colo rado, Montana, Wyoming. Wisconsin, and Mis souri. The greatest supply of granite in this country comes from Maine and Massachusetts. The Maine granites are mostly found in shades of gray, but there are a number of pink and red granites quarried. In Massachusetts, the dark blue-gray granites quarried in the vicinity of Quincy are the best known. Other noted gran ites conic from Concord, N. II., Westerly. R. 1., Richmond, Va., Iron County, Alo., Barre, Vt., and Saint Cloud. _Minn. Besides granite, the crystal line siliceous rocks include porphyry, syenite, gneiss, and trap. Porphyry makes a very hand some building-stone, showing large crystals im bedded in an amorphous ground-mass, the crys tals usually being of a contrasting color to the ground-mass, and these colors ranging through the shades of pink, gray. red. white. and black. Porphyry is so extremely hard that no com mercial means have been found for cutting and polishing it, but it is used to some extent in rough construction. Massachusetts, New Hampshire. Pennsylvania, Wisconsin, and North Carolina contain fine beds of unusually beauti ful porphyry. Syenites differ from granite in containing no quartz. They are found in con siderable quantities in the United States, and make a very handsome stone. but so far they have not been quarried to any extent. Gneiss is a rock much resembling granite in composi tion, but is unlike granite in having well-de lined planes of cleavage, which allow the rock to lie split into thick slabs. Trap includes a number of crystalline siliceous rocks, generally sombre in hue and very ditlieult to work. Ex cept as crushed for making concrete or road material, or when rut into paving-blocks, trap is seldom used for construction purposes. A dark colored trap commereially known as 'black gran ite' is quarried near Duluth, Minn.: at Keese ville, N. Y.; Vergennes, Vt.; on the Maine coast: and at some other points, and is exten sively used for tombstones.