The use to which any particular marble is put is governed largely by its price and color, though texture or grain often are taken into consideration. The coarsely crystalline white and white clouded marbles of southern New York, Maryland, and Georgia, are used almost wholly for building purposes; the pink and variegated marbles of Tennessee for interiors and for furniture; while the white and blue-grays of Vermont find a large market for interiors, cemetery work, tiling, and, to a much smaller extent, for building.
It was stated before that not all our marbles were changed (metamorphosed) marine sediments. The exceptions are (1) the onyx marbles, which, though composed of carbonate of lime, like the last, are deposited from solution, and (2) the so-called verdantique marbles, which are mainly altered eruptive rocks. These last differ widely from those we have been describing, being of a prevailing green color, though often variegated with white or red. They are, in fact, not to be classed with the lime rocks at all. The names verdantique, verte antique, and verde antique are but varying forms of the same words, indicating a green antique marble. The term antique has been applied simply because stones of this type were used by the ancients, and particularly by the Romans.
The so-called onyx marbles are, as noted above, spring deposits, differing from ordinary lime deposits only in color and degree of compactness. The name has also been made to include the stalagmites and stalactites in caves, such as were used by the ancient Egyptians in the construction of alabastrons, amphoræ, funeral urns, and various household utensils. The material is translucent and often beautifully clouded and veined in amber, green, yellow, and red colors. Owing to its mode of origin it shows a beautiful wavy banding, or grain, like the lines of growth in the trunk of a tree when cut across the bedding. This fact, together with its translucency, has been the cause of the wrong use for it of the name onyx, which properly belongs to a banded variety of agate. Equally wrong and misleading is the name "oriental alabaster," which is commonly applied to the Egyptian variety, the true alabaster being a variety of gypsum.
The larger part of our onyx marbles comes to-day from Mexico, though there are equally good materials of this type in Arizona and California.
The foreign supplies come in part from Egypt. Their use is almost wholly for interior decoration, as wainscotings, and the like, and for tops to small stands, bases for lamps, and so forth. These are by far the most expensive of all the stones to which the name marble is properly applied.
Some of the most noted of our foreign marbles are those of Carrara, Italy, which are ancient sediments thought to have been changed at the time of the uplifting which formed the Apennines. They are of white and blue-gray colors, sometimes beautifully veined. A beautiful, mellow yellow to drab variegated variety, very close in texture and almost waxy in appearance, is found near Siena, and is known as Siena marble. It is a great favorite for interior decorative work, as may be seen to advantage in the vestibule of the new public library building in Boston, and the rotunda of the National Library building at Washington.
Other marbles, which at the present time are great favorites with the architects, are the so-called Numidian marbles, from Algeria. These are of yellow, pink, and red color, and often beautifully mottled. Their textures are so close that they take a surface and polish almost like enamel. Since their first hardening these beds have been shattered like so much glass into countless angular fragments, and then the whole mass, with scarcely any disturbance, once more cemented into firm rock. The result is such that when large blocks are sawn into slabs, and the slabs then polished and spread out, the same series of veins, of angular blocks and streaks of color, may be traced from slab to slab, even repeating themselves with only slight changes throughout the entire series.—Nature and Art.
THE WHIPPOORWILL.
MRS. MARY STRATNER.