A group of rare Banco de Portugal partial banknote progressive die proof engraver's test strikes for a five hundred escudos note, circa 1987-1994, comprising four portrait vignettes of José Xavier Mouzinho da Silveira in dark/light brown, as used on the obverse of the note, and two strikes of the reverse in purple with central sheaf containing sunflowers, wheat and grape vines, values to all corners, all on oversized paper/card with near full-plate margins (all extremely fine). Provenance: from the personal archive of the late Alan Dow, master banknote engraver to Bradbury Wilkinson & Co and the Bank of England.