Nov 1861 20l. No C.N. Solid background (Fond uni) deepest blue black of Athens---A GREAT RARITY!!! Probably the only stamp with 4 margins surviving from the unique sheet bearing Fond Uni impressions used in Athens with the heavily printed deepest shade that approximates a deep indigo. The stamp is signed "Orestis Vlastos". Sheet position 109. A rarely seen stamp in any condition, thus extremely importand, regardless of its superior Appearance with no defects.