Scrapbooks can be purchased with acid-free paper leaves, but few people know about them when they start a scrapbook. The best way to preserve the contents of the scrapbook is to remove the items, but this is often impossible due to the tapes and adhesives used. The next best thing is to photocopy the contents or microfilm it. Indexing the contents is another problem. It is best not to start a scrapbook, but if you must do it use acid-free paper and use only photo corner mounts to attach the items.
Leather is beautiful but it requires care.
In our climate a leather bound book should be reoiled every 2-4 years, but only with oils made for rare books. Read about the proper way to first buffer the leather to help it resist acid deterioration and follow with the oiling. Photographs are very fragile. Most color dyes will have color shifts within 20 years. Slides fade and are liable to fingerprints.