1st of January 1877 the Norwegian Postal Department issued a new value of 25 øre, in a new series of posthorn stamps. This stamp was intended for single weight letters sent to far off countries, and is today usually found on covers sent to America (United States). The emigration to the United States started in the countryside, especially in inner fjords in western Norway and upper mountain villages in eastern Norway. Immigration then spread to large parts of the country, and eventually there was just as much emigration from the cities as from the villages. Large population growth and relative overcrowding, especially in the countryside, contributed to increased emigration, along with economic crises, especially from the 1870s. A new need for postal services was visible in this new stamp and it had a fairly large printing volume of 2 million stamps.
One consequence of this use, is the fairly few surviving stamps we have left today, and even more so, we have few of them with the original colour they were produced with. This stamp simply does not like sunlight!
Visible from the three examples here, sunlight wrecks havvoc on the pigments of the ink they were made with. They pale fairly fast, quite similar to the Swedish stamp facit 22 (Facit 22f) produced in the same period. Surely there was an unknown chemical factor here in the make-up of the colours they used.
The consequence of this? Do not go out on the porch in sunlight to marvel at your old stamps. Winter is a good time for philately!