The stamps can occur in many additional colour shades. Most of the inks are water-soluble, so some soaked examples may appear faded.
A premium is justified for plate flaws.
Double impressions, machine set-offs and sheet set-offs may occur and can add substantial value.
On the 1-korona denomination, show-through or bleed-through of the print is common (the red ink is also visible on the reverse). This is a normal characteristic of this denomination and does not add value.
Marginal printing control marks or sheet-total numbers may also add value.
Forgeries:
Unused stamps are very rare, so regumming is known!
