1964-70 "Timbre" Revenue Issue
These stamps were printed by the American Bank Note Co. and were presumably forwarded to Bradbury Wilkinson as samples.
Proof DIE PROOFS: The collection (13) each on gummed paper (51x64mm.), comprising 500col. in grey-green (the design crossed through), ultramarine and pale blue (2, two in different states showing faint "COSTA RICA" in yellow); 1000col. in purple vignette only, complete though without value (3, two states, one showing country name), and complete (3 different, two showing country name), and a further proof with country name only.
Details
Proof DIE PROOFS: The collection (13) each on gummed paper (51x64mm.), comprising 500col. in grey-green (the design crossed through), ultramarine and pale blue (2, two in different states showing faint "COSTA RICA" in yellow); 1000col. in purple vignette only, complete though without value (3, two states, one showing country name), and complete (3 different, two showing country name), and a further proof with country name only.