By the time of the last one-foot band, the painters were working together to try several methods at once, aiming for a maximum of smalt .
Where the horizontal elements of the paneling collected the most smalt , there is an almost neon glow to the blue.
One pertinent example was an advertisement in the New-York Gazette in 1748 for blue smalt , just in from London.
By that time also artificial blues had been discovered, smalt or cobalt blue which is cobalt aluminate in the 17th century, and then the famous Prussian blue, in 1704.
He took a sample about one-half-inch square that went right down to the bare wood for perusal in the laboratory and discovered that what we had was smalt .
In the meantime, the only room that we know of here or in England completely treated with smalt is the Warner House's parlor bedchamber.
They applied the mauve paint as evenly as possible, so that the thickness of the paint would not affect the amount of smalt it held.
The blue colour of smalt derives from the addition of cobalt oxide to a potash glass melt during manufacture.
The rich green against the blue smalt should make Warner's bedchamber look even more dramatic.
Eighteenth- and early nineteenth-century texts on smalt were also unhelpful, generally failing to describe how to apply it to large vertical surfaces.