unused Block Larger Than four 1 quattrino black on grey, an outstanding and probably unique mint block of twelve (4 x 3) showing the complete crown of the watermark, very fresh with margins practically clear on all sides and virtually full original, crackly gum; two negligible splits at foot are mentioned for accuracy. A splendid and extremely fine showpiece. Enzo Diena certificate (1988) stating that this is the largest known block. Signed Alberto Diena, F. Grioni, E. Asinelli. Sassone 1. Photo