When choosing decorative paper sheets for archival work, look beyond color and texture. Check whether the paper complies with ISO 9706, a permanence standard. Its pH should fall between 7.5 and 10, and it should contain an alkaline reserve of at least 2%, commonly measured as calcium carbonate equivalent. That reserve helps neutralize acids absorbed over time. A neutral-looking sheet is not enough.
Ask for a technical specification or test report rather than relying on a product description. Confirm that the figures apply to the paper itself, not just its backing. Coatings, dyes, and surface treatments can age differently, even when the base sheet meets the standard. Keep a sample beside a window or under a desk lamp for a few days; this is not a formal test, but it can reveal quick fading or surface changes. A small check.
ISO 9706 compliance does not guarantee that every decorative component is archival. Consider the intended use: a sheet mounted in a protected album faces different conditions from one exposed on a wall. Check that adhesives and other materials are also suitable for long-term storage. I would not treat a single number as a guarantee. It is useful evidence, but the whole construction matters.