A group of four Central Bank of Trinidad and Tobago banknote die proof engraver's test strike vignettes, colour trials in brown/orange with depiction of a long-billed starthroat hummingbird, as used on notes issued circa 1977, on oversized paper with full-plate margins, together with a further six similar studies of a piping guan on a branch in black, as used on ten dollars notes issued circa 1985, on oversized paper/card (all extremely fine, some light handling marks). Provenance: from the personal archive of the late Alan Dow, master banknote engraver to Bradbury Wilkinson & Co and the Bank of England.