What are the proper conditions of postal stamp storage?
A stamp is a fragile collectible. Improper storage leads to collection price drop. The most important factors that have an adverse effect on the safety of stamps are air humidity, the position of stamps and light exposure.
Stamps feature all the properties inherent in paper. Bright lighting is one of the reasons that contributes to its aging. Avoid direct light striking upon the stamps. Keep them in a dark place. Use a separate cabinet for stamp storage placed away from heating appliances.
The temperature in the room where the stamps are stored (the same is true for other philatelic materials), should be in the range of 15-24 °C and relative humidity within 50-65%. When humidity is less than 50%, paper and glue dry out and become more brittle, and when it is greater than 65%, it creates favorable conditions for bacteria. Stamps must be kept away from heating appliances. Stuffy, stagnant air, tobacco smoke, dust, naphthalene vapors also produce an adverse effect on paper and paints, hence, stamps cannot be stored in wardrobes. In the room where your stamps are stored, you should not cook food, wash and dry clothes. Besides, the presence of large aquariums and houseplants is equally undesirable, airing in rain or very damp weather should be short. You can even neither cough nor sneeze over stamps because saliva droplets that fall on the stamps can contribute to the fungus growth, since a number of bacteria can be added to the paper and glue already in the course of production and they only wait for favorable conditions for growth.
Stamps need to be kept in stockbooks of high quality. When purchasing a stockbook, it is important to pay attention to the quality of the cardboard. Its surface must be smooth, not fleecy, so that the adhesive side of the stemp is not spoiled. It is also necessary to check stability of paint on the cardboard. To do this, rub the surface with a damp cloth or paper. No traces of paint can be left on them. Currently, you can also buy separate stockbook sheets, which are useful for stamp storage.
It is important to arrange stamps properly in a stockbook. It is desirable to avoid placing the stamps in stockbook strips “in overlap” because it can result in their sticking and deformation. It is unallowable to overload sheets with stamps, because it will lead to deformation of strips and the stockbook proper. Before the most valuable stamps are placed in a stockbook, it is advisable to put on protective “klemmtasche” on them. It is reasonable to store oversized blocks and stamp sheets in plastic protectors for ordinary transparent files, which are preloaded with dense paper sheets.
Albums and stockbooks cannot be stacked. Stockbooks and albums must only be stored in an upright position (similarly to books on shelves), they should not be tightly pressed against each other, and they should not be piled up in any case. This may result in the stamps sticking together and getting glued to sheets; moreover, stockbook strips will be imprinted on them, etc. In addition, such kind of storage deprives the stamps of a possibility “to breathe”, which is a necessary condition for stamps, because otherwise paper will dry up and lose elasticity. Stockbooks, albums, folders with philatelic materials should be "aired" regularly by turning over the pages.
Similarly to any things brought from frost into a warm room, stamps will “fog up”, and if you bought stamps in winter, before placing them in a stockbook or album at home, keep them at the room temperature for about half an hour, turning them over with tweezers from time to time to evaporate the excess of moisture.
None of these precautions should scare away would-be philatelists. In practice, stamps "get sick" in very rare cases. In hands of any experienced philatelist, even the oldest stamps look like new ones.