The colours are vitrified and slightly in relief; green, blue and brown may be distinguished.
On the coast of Loch Nell, or Ardmucknish Bay, is the vitrified fort of Beregonium, not to be confounded with Rerigonium (sometimes miscalled Berigonium) on Loch Ryan in Wigtownshire - a town of the Novantae Picts, identified with Innermessan.
The coral limestone of the atoll has a peculiar vitrified appearance and gives out a ringing sound when struck or simply walked on.
Vitrified fort, 390 ft.
The process was known at an early period, and was employed for the purpose of subsidiary decoration from the close of the 16th century, but not until the 19th century did Japanese experts begin to manufacture the objects known in Europe as enamels; that is to say, vases, plaques, censers, bowls, and so forth, having their surface covered with vitrified pastes applied either in the chain plev or the cloisonn style.