In order to impress gilt figures, letters, and other marks upon leather, as on the covers of books and edgings for doors, the leather must first be dusted over with very finely-powdered dried white of egg, yellow rosin, or mastic gum, upon which lay a leaf of gold. The iron tools or stamps are now arranged on a rack before a clear fire, so as to be well heated, without becoming red hot. If the tools are letters, they have an alphabetical arrangement on the rack. Each letter or stamp must be tried as to its heat, by imprinting its mark on the raw side of a piece of waste leather. A little practice will enable one to judge of the heat. The tool is now to be pressed downwards on the gold leaf, which will, of course, be indented, and show the figure imprinted on it. The next letter or stamp is now taken and stamped in like manner, and so on with the others; taking care to keep the letters in an even line with each other, like those in a book. By this operation the rosin is melted; consequently, the gold adheres to the leather; the superfluous gold may then be rubbed off by a cloth, the gilded impressions remaining on the leather. The cloth alluded to should be slightly greasy, to retain the gold wiped off; the cloth will thus be soon completely loaded with the gold.
When this is the case, these cloths are generally sold to the refiners, who burn them and recover the gold.