II.—Remarks on the Formation of Landscape Marble

Extract

The Landscape Marble or Cotham Stone is one of the best known of our English ornamental rocks. Polished slabs of it may be seen in most museums; and there are fashioned out of it paperweights, ring-stands, and other useful objects, which may be purchased on Clifton Down and elsewhere.

This stone came into notice when it was quarried, together with other beds, near Cotham House, on the northern side of Bristol; and it was described in considerable detail in 1754 by Edward Owen, who then gave it the name of “Cotham Stone.”

It is a hard, close-grained argillaceous limestone, which breaks with a fracture almost as conchoidal as that of flint; and it is characterized by dark arborescent markings which pervade the stone. These markings rise from a more or less stratified base, and terminate upwards in the wavy banded portion of the limestone, which varies from one to about nine inches in thickness. Thus when slabs, cut at right angles to the planes of bedding, are polished, there may often be discerned (with the aid of the imagination) a landscape with a prominent row of trees and bushes, with clouds above, and perhaps the semblance of water in the foreground.