Mould damage to books left in a damp and humid environment

Foxing, flaking, red rot, blanching, silver mirroring, mould. Are you wanting to accurately describe the condition of an item and confused about what terms mean what?  The Australian Institute for the Conservation of Cultural Material (AICCM) has a visual resource online that shows you what various types of damage and deterioration look like. You can see the visual glossary here.