When Queen Victoria and Prince Albert bought Balmoral Castle, the Queen discovered the jewelry called pebble, that is agate, jewelry. The Queen was a fashion maker, and everyone followed. This brooch has 7 pieces of agate, a detailed sterling buckle, surround and garter tab as well as the backing. 2 1/4" tall and 1 3/4" wide. Old style C clasp and long pin stem which extend beyond the edge of the brooch. This is a signature of a Victorian brooch. Not marked, as these pieces were not. Acid tested as sterling. The agates are superbly set. No chips. Victorian. Late 1800s.