Watch List notes:

GREECE: 500 Drachmas (1988) in silver (0,900) commemorating the 28th Chess Olympiad. Composition with chess table and inscription "28η ΟΛΥΜΠΙΑΔΑ ΣΚΑΚΙΟΥ ΘΕΣΣΑΛΟΝΙΚΗ 1988" on obverse. Inside slab by NGC "PF 68 ULTRA CAMEO / CHESS OLYMPICS". Cert number: 5790781-001. (Hellas CD.24).