These are antique glazed tile made by J. & J.G. Low Art Tile Co. of Chelsea, Massachusetts. These feature an acanthus leaf design glazed in dark amber brown. It's shown in their 1884 catalog as design X38, image is attached. Multiples are available.

History of J. & J.G. Low:
1835. John G. Low, inventor of Low's Art Tiles, born at Chelsea, Mass.
1861. He finishes a course of several years study in the Ateliers of Couture and Troyon, in Paris.
1862. He returns from Europe to America.
1865. First gives his attention to scenic and decorative painting, which he pursues for several years.
1873. Begins experiments in making pottery, and becomes absorbed in the study of ceramics.
1871. Forms co-partnership with his father, Hon. John Low, and ground is broken for the erection of a Tile factory.
1879. May.—The first successful firing of a kiln of Tiles is accomplished.
Sept.—Exhibition made at Cincinnati Industrial Exposition, and the capital prize, a silver medal, awarded Low's Art Tiles.
1880. August 10.—Circular received from England announcing competitive exhibition at Crewe, near Stoke-on- Trent, of English and American Tiles, offering gold medal, value of £10, for the best collection of Art Tiles. A silver medal to be awarded the second best collection. (This announcement was received but two days before the sailing of the steamer, and the entry for competition was immediately sent forward by cable.)
August 12.—The examples for completion, hurriedly selected from a meagre stock, were shipped by Ocean Express to Crewe.
Sept. 2.—Opening of the International Competition at Crewe.
Sept. 3.—Receipt of cablegram, " Low Won Gold Medal.''
Nov. 18.—U. S. Consul Packard of Liverpool says in Consular report: " The gold medal was awarded this collection -(of Low's Tiles) over the most famous pottery manufacturers of the United Kingdom.''
Dec.—Bronze medal awarded by American Institute, New York.
1881. Oct.—Special award of silver medal made by St. Louis Agricultural and Mechanics' Association.
Nov.—Gold medal from Massachusetts Charitable Mechanics' Association.
1882. June 15.—Opening of Exhibition of Low's Art Tiles and Plastic Sketches, at Rooms of the Fine Art
Society, in New Bond Street, London.
June 17.—Visit of their R.H. the Prince and Princess of Wales, Sir Frederic Leighton, and other notables, to Low's Exhibition, in New Bond Street.
1882. June 17.—The London Court Journal says: "This gentleman (Mr. Low,) has invented a new species of ceramic ware. The first which America has produced in any high order."
June 10.—The London Daily News says: "The)' seem to be not only beautiful, but to reveal a new phase in art, somewhere between sculpture and painting."
July 6.— The Pall Mall Gazette says: " It will be seen that they are by no means an imitation of the Delia Robbia ware, but a fresh departure." October.—Gold medal from the Cincinnati Industrial Exposition.1883. Hon. John Low retires from the firm, and Mr. John F. Low, son of the inventor, becomes associated with his father under the firm name of J. G. & J. F. Low.
NOTE.—We publish this Chronology in order to answer the innumerable letters and inquiries for a history of our work, which seem to be inspired by a world-wide interest in our success.