Paper produced in the late 19th and throughout the 20th centuries varies a great deal in quality and life expectancy. Daily newspapers degrade visibly in a matter of days, while papers of the highest quality rival the older rag papers in stability. NATIONAL GEOGRAPHIC magazine is printed on 55 pound (81 grams per meter squared) paper coated with a standard latex/casein/clay coating, and bound in a 100 pound (148 grams per meter squared) cover stock with a similar coating. This paper and the synthetic inks used assure a long life expectancy for the magazine.

But all organic materials deteriorate as they age, so proper care and handling are essential to maximize the life of your collection.

The state of preservation, the life expectancy, and the value of your collection are affected by these factors:

• storage conditions
• the storage materials in which you store your collection handling practices
• exposure to light through display
• the prevention and repair of damage.