Overprint type I - top of frame curved at right side. Overprint often placed over two or more stamps due to size, so smaller single stamps may only show part of the overprint. Beware of forgeries. Best collected on piece or on full cover. Expertisation highly recommended. Overprint on Mi: FR 439
Printed in sheets of 50 stamps.
Exists according to the Yvert catalog:
- 无孔 (一个).
Varieties: 421第一: dark blue, 421B: blue-green
Both stamps are distinguished from N° 421 by their colors, but also substantial differences in the engraving.
Features of the landscape in the background more acute, acute-angled right eyebrow, the checkered jacket-less distinct and hatch in the letter R.
