1840 RAINBOW TRIAL IN BLACK ON WHITE WOVE PAPER IN PRUSSIATE OF POTASH (SPEC DP20(3)a). A superb upper left corner marginal 1840 rainbow trial in black on white wove paper dipped in prussiate of potash (Spec DP20(3)a) with full sheet margin at left and top. A very rare rainbow trial with only two sheets believed to have been printed and I witnessed this very sheet being cut up in the early 1980s. Exceptional item of exhibition quality. (Ref 138349).
a).){kind=link}
