Proof 1920 Tercentenary, die proof of the vignette in black on glazed white card (92x60 mm.), marked "BEFORE/HARDENING" and dated "26/7/20" in pencil; fine and rare

Details
Proof 1920 Tercentenary, die proof of the vignette in black on glazed white card (92x60 mm.), marked "BEFORE/HARDENING" and dated "26/7/20" in pencil; fine and rare
Provenance
Henry D. Hicks, 1975