The word vellum used to mean a thin parchment made of animal skin. To modern scrapbookers, vellum is the translucent paper that creates elegant effects on album pages. But depending on how it gets that delicate translucence, vellum can be bad for photos — even if it is acid- and lignin-free.

Some vellums are made translucent through the application of petroleum-based resins that can cause photos to deteriorate, says Bob Toth, vice president of marketing for Canson <www.canson-us.com>. Other vellums — such as Canson's — are made transparent through a safer nonchemical process.