Italy - Postcard for a prize competition with postage at the rate that includes the rare 100-lire Castelli - Sassone specializzato N. 1511/IV

Competition folder for Milan dated 14-7-1992, prepaid in the 700 lire tariff with the 100 lire Castelli stamp printed in error on non-fluorescent paper and with watermark Stars II. The stamp in used, loose condition is valued at €200.00, but on a document traveled in the tariff, certainly not philatelic, it is not common and has a clearly higher value, even though it is not specified in the common catalogs (Bolaffi included).