Restoring postage stamps can be accomplished most delicately with sophisticated tools in the hands of a professional conservator. Even the innocent application of transparent tape by an amateur has caused yellow bleed-through when placed on the back of stamps. There are some simple remedies for stamp restoration, but the integrity of the paper and ink needs to be first and foremost in mind when handling a stamp collection. The value of a stamp collection can be jeopardised by improper handling and amateur restoration attempts.
Test the ink on one small corner to make certain it is insoluble and will not run. Old inks are usually stable.
Clamp the stamp to a nonmetallic screen with a nonmetallic clamp.
Mix four drops of clear liquid soap into one pint of water. Make certain that there is no colour in the soap. Immerse the clamped stamp slowly into this solution.
Press the water from the clean stamp on white blotter paper.
Place the stamp between two sheets of white blotter paper when all the moisture is removed.
Set a medium-weight book on top of the stamp and allow it to sit overnight.
Remove pencil marks by gentle rubbing with powdered pumice on a cotton swab. The paper may be too weak to handle this action without compromise.
Add alum to hot water to remove stains. Immerse the stamp into this solution and delicately rub the stain with a cotton swab. Rinse in clear water, blot and press.
Place the stamp on white blotter paper.
Use a white pencil eraser to gently rub the stamp. Do not use vigorous motions in this erasing; in fact, be gentle so that the paper does not become compromised. Faber-Castell Magic-Rub #M-196 is a good eraser to use in this procedure. Be sure to keep a clean edge on the eraser.
Brush with a soft shaving brush to remove loose dust.
Sprinkle Draughtsman's cleaning powder over especially difficult dirt.
Use a circular motion and the soft brush to move the powder from the centre of the dirty spot to the edges.
Use cotton balls instead of your fingers to handle the stamp and brush off the powder with the soft brush.
Cancellation marks will often wash off with wet cleaning. Be certain of the future value and consequences before you begin any postage restoration process.