США 1901г. № 228 гашеная

США 1901г. № 228 гашеная    Перфорация: 12 90 The one cent stamp portrays the steamship "City of Alpena" which operated along the Great Lakes. The stamp was printed in two steps, first the vignette, the illustration of the steamship, was printed in black and then the frame surrounding it was printed in green. Since it was difficult for the printer to place the sheets in exactly the correct position for the frame to be printed perfectly centered, some misregistration was to be expected. In fact, the ship may appear nearly anywhere in the frame, leading to highly collectible items such as "fast", "slow" and "sinking" ship varieties. But the most collectible variety is the one in which the frame was actually printed upside down! These are known to collectors as "inverted centers" and are highly sought after.