The name of a German city. attrib. in Frankfort black, a fine black pigment used in copper-plate engraving.
1823. J. Badcock, Dom. Amusem., 28. The black which is made by sublimation of pitch in dark chambers, and termed lamp-black and Frankfort black.
1853. Ure, Dict. Arts, etc., I. 814. Frankfort black is made by calcining vine-branches, and the other refuse lees of the vinegar vats, in Germany.
