Store old maps flat, in acid-free folders or Mylar sleeves, in a dark, cool and steady room. Avoid folding, rolling tightly, tape, sunlight and damp basements. Handle them with clean, dry hands and support the whole sheet when you move it.
The enemies of old paper
- Light. Sunlight and fluorescent light fade inks and hand coloring and weaken paper.
- Damp and heat. High humidity brings mold and foxing (brown spots); dry heat makes paper brittle.
- Acid. Cheap cardboard, wood and ordinary paper envelopes pass acid into the map and turn it yellow-brown.
- Handling. Folding, rolling and sliding sheets cause tears and creases.
Storing maps flat
Lay each map flat in an acid-free, lignin-free folder or an archival polyester (Mylar) sleeve, then in a flat box or a shallow drawer. Don't stack too many maps in one folder. Large maps that are already folded can stay folded rather than being forced flat; if a fold is splitting, that's a job for a paper conservator.
Rolling large maps
If a map is too big to store flat, roll it loosely, image side out, around a wide acid-free tube, with archival tissue between layers. Store the roll horizontally and avoid squeezing it.
Framing and display
Use a framer who works with archival materials: acid-free mats and backing, the map hinged rather than glued, and UV-filtering glazing. Hang it away from direct sun, fireplaces and bathrooms, and consider rotating displayed maps so no single one gets years of light.
Handling
Wash and dry your hands (clean cotton or nitrile gloves are fine but can make you clumsy), support the map with a sheet of card when lifting, and never use tape, glue or paper clips. Keep food and drinks away from the table.
Questions
Should antique maps be stored flat or rolled?
Flat is best, in acid-free folders. Roll only maps too large to store flat, loosely and image side out.
How do you protect an antique map in a frame?
Archival mat and backing, hinge mounting and UV-filtering glass, away from direct sunlight.
Can I clean an old map myself?
Only light surface dust with a soft brush. Stains, tears and foxing need a paper conservator.