ARTIFICIAL MARBLES. The stucco, of which statues, busts, basso-relieves, and other ornaments of architecture are made, ought to be marble pulverized, mixed in a certain proportion with plaster; the whole well fitted, worked up with water, and used like common plaster. See STUCCO.
There is also a kind of artificial marble made of the flaky selenites, or a transparent stone resembling plaster, which
Marble. which becomes very hard, receives a tolerable polish, and may deceive a good eye. This kind of selenite resembles Muscovy talc.
There is another sort of artificial marble formed by corrosive tinctures, which, penetrating into white marble to the depth of a line or more, imitate the various colours of other dearer marbles.
There is also a preparation of brimstone in imitation of marble.
To do this, you must provide yourself with a flat and smooth piece of marble: on this make a border or wall, to encompass either a square or oval table, which may be done either with wax or clay. Then having several sorts of colours, as white lead, vermilion, lake, orpiment, masticot, smalt, Prussian blue, &c.; melt on a slow fire some brimstone in several glazed pipkins; put one particular sort of colour into each, and stir it well together; then having before oiled the marble all over within the wall, with one colour quickly drop spots upon it of larger and less size; after this, take another colour and do as before, and so on till the stone is covered with spots of all the colours you design to use. When this is done, you are next to consider what colour the mass or ground of your table is to be; if of a gray colour, then take fine sifted ashes, and mix it up with melted brimstone; or if red, with English red ochre; if white, with white lead; if black, with lamp or ivory black. Your brimstone for the ground must be pretty hot, that the colour dropt on the stone may unite and incorporate with it. When the ground is poured even all over, you are next, if judged necessary, to put a thin waistcoat board upon it: this must be done while the brimstone is hot, making also the board hot, which ought to be thoroughly dry, in order to cause the brimstone to stick the better to it. When the whole is cold, take it up, and polish it with a cloth and oil, and it will look very beautiful.