BTJILDING-STONE. 650 BUILDING-STONE. black. Dolomitie limestone, or dolomite, is a spe- cies which contains mafrnesia in addition to car- bonate of lime. The distinction between limestone and marble is one of (|uality rather tlian one of composition, marble beinfr a crystalline limestone capable of taking a hiah polish, and having a coloring or marking which adapts it to orna- mental work. The coarser grades of limestone are widely distributed, and nearly every State of the United States has quarries which are worked to supply at least the local demand. Perhajis the most w-idely kno i of the lime- stones of this country are those of Indiana and northern Kentucky. These are oolitic limestones; they are very fine and even in texture, strong and easily worked, and of handsome color. This limestone is po]>ularly known as "Bedford stone.' At Lamont and Joliet, 111., there are also not- able quarries of finegrained, light-drab lime- stone, which is extensively emidoyed. Among the foreign limestones, the Portland stone, from the Isle of Portland, England, has been favor- ably known for a great many years. It W'as used in the reconstruction of Saint Paul's Cathedral. The Caen stone (q.v.) of France is one of the most noted limestones of the world. It is a soft, fine-grained stone, very light colored, admirably adapted for carved work, but so ab- sorbent as to be entirely unfitted for out-of-door work in a cold climate. The stone is quarried near Caen, Normandy. The principal sources of American marble are in the States bordering the Appalachian Moim- tains, and particularly Vermont, ilassachusetts, western Connecticut, eastern New York, Georgia, and eastern Tennessee. Nearly 60 per cent, of the marble quarried in the I'nited States conies from Vermont. Vermont marbles range through all varieties of texture and various shades of color, from pure, snowy white to quite dark- bluish and greenish stone, the white stone often being beautifully mottled and veined with the darker stone. The 'principal centres of the Ver- mont marble induslrv are West Rutland, Dor- set, Wallingford, Pittsford, Brandon, and Mid- dlebury. Next to the Vermont marbles, those of Tennessee merit the most particular notice, because of their beautiful variegated colors, among which are found chocolate, red, pink, olive, green, brownish-red with white spots, gray with lemon spots, and other combinations of colors. Georgia contains very large marble de- posits, some of which furnish very beautiful stone, and this, with the fact that the climate permits (luarry-ing the year roiuid, is developing an active'marble industry in tliis State. Besides the Appalachian marl)les, there are deposits of this stone in several of the Rocky Mountain States, but these have not been nuich worked. Among the most notable foreign marbles are the brilliant red marble found at several locali- ties in the French Pyrenees, and the Languedoc marble, having a brilliant scarlet color blotched ■with white, found at Black Mountain, in the Pyrenees. Broeatelle marble, having a light yel- low Ijody traversed by irregular veins and blotches of dull red, is another famous French marble. Belgium is exceptionally rich in col- ored marbles, but white is not found. The deep blue-black marble with white veins, known as Saint Anne marble, and the pure Idack niarlde, known as Belgian black, are i)arti(ulnrly well- known Belgium marbles, ilost of the other Bel- gium marbles are dull red, of light and dark shades, variously sjiotted. flecked, and veined with white and gray. The Italian marbles are proverbial for their quality and variety. The two most noted are the white statuary marble with its fine grain and pure color, which, when polished, gives a waxy appearance found in no other marble: and the Siena marble with a bright yellow ground blotched with slight pur- plish ami violet shades. The black and gold marble, with a black ground carrying yellowish and reddish veins, is another noted Italian mar- ble. Germany, Spain. Portugal. Austria, and Ireland furnish marbles notable for texture and color. A form of marble — variousl- known as onyx, or onyx marble, or alabaster, but really a travertine formed by the evaporation of water holding carbonate of lime in solution — is found extensively in Algeria and Mexico, and is much used for table-tops and other small decorative and ornamental work. A good quality of on-x marble is found in Arizona and Southera Cali- fornia, in the United States. Sakd.stones. Sandstones (q.v.) are composed of rounded and angular giains of sand, so ce- mented and compacted as to form a solid rock. The cementing materials are silica, oxide of iron, and carbonate of litne. Silica cement gives a white colored stone, very firm and durable, but difficult to work: oxide of iron cement gives a brownish or reddish stone of fair durability and fairly easy to work: and carbonate of lime gives a grayish stone soft and ea.sy to work, but less durable than when either oxide of iron or silica forms the cementing material. Some sandstones have a clayey cement, which is more objection- able than any of the others, and other sand- stones contain little, if any, cement, owing their tenacity to the pressure under which they were consolidated. Often the cemented grains com- prise feldspar and mica, as well as sand. The texture of sandstones varies from exceedingly fine-grained stones to those composed of pebbles of various sizes. The latter are called conghmi- erates if the grains are rounded, and breccias if they are angular. Sandstones vary in color; light gray, bufV, drab, blue, brown, pink, and red being the colors of well-knowm varieties. Sandstones generally are softer when (juarried than after a period of seasoning. (iood sandstone for" structural purposes is found so widely distributed in the United States tliat it is impossible to mention all of even the notable deposits. The Berea stone, of Ohio: the ^ledina stone and bluestone. of New York: the Portland stone, of Connecticut and Massaclui- setts; and the red and brown sandstones, of New Jersey, are among the most extensively quar- ried and best known. Of the foreign sandstones the variety is quite as great as in the United States. Sl.te. Slate is an indurated siliceous clay which easily splits into sheets of considerable thiimess. It is ised chiefly for roofing purjioses, mantles, floor-tiles, and flagging, billiard-tables, sinks, and blackboards. Slate is quarried in a number of States, but principally in Maine, New York, Pennsylvania, and 'crmont, the produc- tion of the last two States being the greatest. Since ISO" the United States producers have be- gun to build up an export trade which bids fair 1
