10 Drachmas (1968) (type I) in copper-nickel. Head of King Constantine II facing left and inscription "ΚΩΝCΤΑΝΤΙΝΟC ΒΑCΙΛΕΥC ΤΩΝ ΕΛΛΗΝΩΝ" on obverse. Inside slab by NGC "MINT ERROR MS 61 / CLAMSHELL LAMINATION". Cert number: 5788846-017. (Hellas 234).