Preservation and Care of Philatelic Materials
Subsidiary Page
8
Dry Cleaning of Stamps and Covers
One of the favorite methods for surface cleaning old covers is to use an eraser and brush.
There is no type of eraser which does not, to some extent, damage the paper surface from
which dirt or markings are removed. One of the chief concerns in cleaning is the removal
of pencilled notations on the reverse of a stamp. These are usually perforation notes,
catalogue numbers, and sometimes even catalogue prices. Many misguided collectors
pencil these marks on the back of stamps as well as on covers. Such marks are even
occasionally seen in ink, which very likely means that the philatelic item is permanently
damaged and, often, dramatically reduced in value. There is no method of removing
pencilled notes and markings that is completely harmless to the philatelic item.
While most stamps are printed on high quality paper which will stand up fairly well to the
abrasion that results from the erasure of markings, there is still some fragmentation of the
surface. On poor quality papers the abrasion is much more pronounced. Old stamps and
covers, often brittle or flimsy, are easily torn or creased in the effort to remove pencil
marks. Even when some pencil marks are erased, a groove or indentation from a hard
pencil will remain. A candidate for the removal of a pencil notation is the cover shown in
Figure 11.
Figure 11. Example of a cover whose appearance would be
improved by
careful cleaning and removal of pencil notation at upper left.
The 1898 postal history item shown in Figure 11 is of a size that it could be attractively
mounted on an album or an exhibit page. The appearance of the cover, however, would be
greatly benefitted by the removal of the pencil notation at upper left, a notation which is
probably the catalogue number of the stamp and possibly the valuation of the stamp when
the notation was added. In this case, careful erasing of the pencil notation would be in
order. The surface dirt on the cover also needs attention.
Covers sometimes require a light brushing with a dry soft shaving brush to remove loose
dirt or dust. General surface dirt that is more difficult to remove can often be dislodged
by using a draughtsman's cleaning powder. One of the powders recommended is "SKUM
X" by Dietzgen. Sprinkle the granulated erasing powder over the area to be cleaned.
Work over the surface with a gentle circular motion, moving the center towards the edge.
Use a small ball of absorbent cotton. Do not use your fingers because the oils, moisture,
acids and salts present in the skin might be transferred to the paper. To remove the
powder, use a soft brush, working from the center out, brushing in one direction.
To remove graphite or soft pencil markings, you may have to use an eraser, even though a
minimal slight surface damage will result. It is very important that you select the proper
type of eraser in order to minimize surface damage. Most erasers are made from rubber
or polyvinyl chloride. Some erasers contain very harsh abrasives. We should select a soft
eraser in order to minimize surface damage and abrasion. Two of the more effective vinyl
erasers are "MARS-PLASTIC" by Staedtler and "MAGIC-RUB" by Faber-Castell.
Figure 12 illustrates the low amount of damage caused to a cover by a "MAGIC-RUB"
eraser.
Figure 12. Eraser residue from a MAGIC-RUB block eraser magnified
100
times. Residue and fiber damage are relatively low.
When an eraser is applied to a stamp or cover, support the philatelic item by placing it on
blotting paper. When the eraser becomes rounded
from use, cut it to a clean edge. Remember that several gentle rubbings are far better than
a single vigorous one. An old plastic eraser shield may be very helpful. Avoid using
colored erasers because colored residue often becomes trapped on the surface being
cleaned. Do not use the eraser too vigorously since it will tend to smooth and burnish some
papers.
Special care should be taken when working with proofs. Proofs are usually engraved on
very thin fine India paper, often called "chin applique' or "chine calle." After printing,
the India paper is pressed onto a heavier piece of paper. They are held together by the
compression of the fibers. No adhesive is employed. An eraser can be used on the support
paper but not on the delicate thin India paper. Careful testing will indicate whether a
light application of cleaning powder can be used for cleaning purposes.
A 1981 research report prepared by the Analytical Research Service of the National
Museums of Canada indicates that a block eraser works best. This report notes that soft
rubber erasers harden with age, and polyvinyl chloride (PVC) erasers slowly degrade. The
study further determined that Pink Pearl, Opaline, Kneaded Rubber, and Magic-Rub
erasers left detectable amounts of eraser material on the paper. A good brand of eraser to
use is Faber-Castell Magic-Rub #M-196, which is a white pencil-type of eraser.
Faber-Castell Magic-Rub #M-196 leaves an exceptionally low amount of residue on
the paper. The residue is low in chlorine, intermediate in amount of silver tarnishing,
and does not contain silica (finely ground sand) as an abrasive. Photomicrographs
show that the complete removal of eraser particles by brushing is unsuccessful.
The Magic-Rub eraser was found to be the most suitable for use in cleaning paper.
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