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Rh but other localities have since been found. Excellent quarries are also found in other parts of the United States. 2. The variegated marbles are those variously spotted, shaded, and veined. They are the most numerous class, and include the most beautiful of the colored marbles. None are more highly esteemed than the variegated yellow marble of Siena. This and the Italian dark red marbles may be seen in many of the costly mantels in our marble shops; and also the soft, shaded, dove-colored Lisbon marble, of which are made the smaller columns in the entrance of the Unitarian church at the corner of 4th avenue and 20th street, New York. The black Genoese marble, with golden-colored and white veins, called Portoro marble, the best of which is from Porto Venese, has for many years past been the most popular and the best known foreign marble in all parts of the United States, though now rather out of fashion. It is a weak stone, and is for the most part used in thin slabs cemented upon a back of slate. The marbles of this class found in the United States east of the Rocky mountains have not attained much celebrity, nor do we know of any worthy of it, unless we should include among them certain varieties of the brecciated marbles from northern Vermont and Tennessee. The gray and white clouded limestones of Thomaston, Me., are quarried to considerable extent for marble, and may be seen in common use in portions of the eastern states. They possess little beauty. California has furnished of this class some very showy marble of brilliant reddish and brownish colors, and susceptible of a high polish. It is imported into New York and used for mantels. 3. The brecciated marbles are composed of angular fragments, it may be of various mineral substances, united in a bed or paste of calcareous cement; or the mass may be so divided by numerous veins into pieces as to present the appearance of broken fragments irregularly united. Brocatellas are breccias, in which the fragments are very small; we incorrectly apply the name only to a reddish brecciated marble brought to this country from Spain. The varieties of this class are very numerous; but some of the most celebrated are never seen here, such as those called le grand deuil and le petit deuil, literally the full mourning and the half mourning. These come from the Pyrenees and different parts of France; they are of a black ground spotted with white fragments. Among the brecciated marbles of the United States, the best known is that of the Potomac on the Maryland side, some miles below the Point of Rocks. The principal use that has been made of it was to furnish the columns in the old chamber of representatives at Washington. The irregularities of hardness in the different ingredients render it an expensive stone to work; still the quarries are deserving of more than government patronage. The stone is certainly handsomer than the Italian red and white breccia imported for the

inner columns of the central arched entrance of the church before mentioned. Quarries have been opened in the northern part of Vermont, near Lake Champlain, which produce the most beautiful of the American colored marbles. They are brecciated, though they pass into the variegated. They present a great variety of colors, from a deep red, traversed with veins of white, to rose-tinted flesh color mottled with whitish spots. In some specimens the brecciated structure is very strongly marked, the fragments being large with sharp edges and of decided shades of dark red, drab, and salmon, upon a ground of white bordered with rose. Unlike the Potomac marble, the fragments are not different varieties of rock, but are all limestone. The stone, though somewhat hard for marble, is still of uniform texture and takes an even high polish. Some large blocks closely resemble the foreign brocatella. It is however very difficult to work. Other marbles of this character and of rather dark red colors abound near Knoxville, Tenn., and have been brought into notice by the extent to which they are employed in the construction of the capitol at Washington. 4. Lumachella or fossiliferous marbles are those which contain petrified shells. These are sometimes so crowded upon one another, that they compose the whole mass of the stone; sometimes single shells are seen scattered throughout the block. These marbles are very abundant in Europe, and also throughout New York and the western states. Handsome mantels are made of American varieties which are composed entirely of fossil shells, but they are rather to be regarded as curious than beautiful. They lack the high colors of the brecciated and variegated marbles, and though they take a good polish, they are from their plain colors comparatively dull and sombre. Some of the best of the kind is from Becraft's mountain, back of Hudson, N. Y., which is thus noticed by Prof. Silliman (“American Journal of Science,” vol. vi., p. 371): “The marble is of a grayish color with a slight blush of red; its structure is semi-crystalline, and in some places highly crystalline, especially in and around the organized bodies which in vast numbers it embraces. The large slabs present a great diversity of appearance, and can scarcely be distinguished from the similar transition marble of the Peak of Derbyshire, which it quite equals in beauty and firmness.”—Serpentine, as before stated, differs in composition from the other marbles. It consists of about equal parts of silica and magnesia with 12 per cent. of water. It is a soft mineral of different shades of green, of waxy lustre, and susceptible of a high polish. It is better adapted to ornamental work within doors than to be exposed to the action of the weather. Verd antique is a mixture of green serpentine and light-colored limestone. These varieties come from Genoa and Tuscany, and the best verd antique from Egypt. In Vermont and Canada serpentine abounds;