exceptional c. 1860's pre-chicago fire interior residential high victorian fireplace mantel marble keystone fabricated by the chicago marble mfg. co., chicago, il. the american sylacauga marble keystone features a centrally located cartouche surrounded by volutes carved in deep relief. the slightly curved mantel piece was salvaged from a chicago mansion located on the gold coast. the oversized white marble keystone remains in great shape, with surface discoloration evident. truly an amazing chicago mansion artifact rescued from a now-demolished residence. measures approximately 8 x 3 x 10 inches.