BY:
- F. Aleem
Sundal
Stamps
are not always printed on paper. Also they are
not always gummed. In Iran, postage has been
printed on gold foil without gum and perforation
but in Colour. There are even examples of stamps
printed in 24 carat gold (Pakistan). Many other
countries have produced stamps with varied
amounts of gold and silver. Self-adhesive and
three dimension stamps are becoming popular in
Arab States and in
Europe.
SHAPES Stamps are produced almost
in all possible geometrical shapes – circular,
hexagon, and octagon, parallelogram, triangular,
square and rectangular. They have taken the
shapes of medallions, country maps, human
figures and even fruit like bananas and
watermelons. But these are exceptions and are
not much popular among serious collectors,
because of their restricted
nature.
PAPER Many of the early stamps
were printed on hand made watermarked paper in
sheets of required size. But most of the later
issues are printed on machine-made paper in
continuous rolls. Naturally early stamps had
greater variations in paper
quality.
There are many
kinds of paper used for stamps, e.g., Laid
paper, Quadrille paper, Granite paper, Toned
paper, Manila paper and Silk Threaded paper,
Shortage of paper in wartime, saw the printing
of postage stamps on currency note paper, on
newsprint and on the backs of poster size maps.
These prints are of immense philatelic interest.
The three most commonly used types of paper
are:
ORDINARY
WOVE PAPER Most of the stamps
are printed on wove paper, having a plain, even
texture, created when pulp is brought in contact
with the finely netted wire mesh of the
papermaking machine.
In developing
countries this type of paper is generally used
for commemorative stamps, as it is comparatively
cheaper and suitable for short-lived items in
limited quantity. It can easily be distinguished
from its printed surface, which is somewhat
coarse and printing not very
sharp.
CHALK
SURFACED PAPER This paper is coated with
a chalky solution and has a glossy effect and is
most commonly used for security documents,
especially stamps. Chalky paper may be
distinguished by a simple test. If touched with
silver, a kind of pencil mark is caused but it
can spoil the stamp. Printing on chalky paper is
very sensitive and the stamp is likely to be
ruined when introduced to
water.
PHOSPHORIZED
PAPER This
is the most recent addition to paper qualities
and is extensively used in European countries
where automatic letter sorting machines are
employed. The prime purpose of phosphor is to
respond to electronic signals from machine
sensors for detection and separation of classes
of mail and also to evaluate the postage being
paid.
PERFORATION A series of holes is
punched around stamps for separation. The number
of holes in each linear inch of any side of a
stamp is called its perforation. Sometimes
compound perforation is punched on a single
stamp, for example, if perforation is described
as, p14 x 15, it means that the stamp has 14
holes at the top and bottom and 15 each on both
sides.
Perforating
machines are of two types and punch holes in two
distinct manners called comb and line
perforation. Perforation pins are arranged in
the form of a “comb”. Vertical and horizontal
rows are perforated at a time and are identified
by the evenness and regularity of the
intersecting holes. But in line perforation,
rows of stamps are punched in single lines,
either vertical of horizontal. The sheet is then
turned sideways on and the process repeated.
Line perforation can usually be identified by
the fact that the intersecting holes at the
corners of stamps never match
precisely.
Many types and
shapes of perforation are used in stamp making.
Round whole perforation has two varieties. Holes
of two or more different diameters are placed in
a row like “comb”.
But a quite
different type of perforation is rouletting.
Roulette is a French word, meaning a tool with
toothed disc or wheel for perforation of paper.
It makes in a sheet of paper, pin shaped,
arc-shaped, tiny cross-shaped, zigzag or
straight cuts, but no portion of paper is
removed.
Among roulette
perforation, the serpent roulette is most
significant. Here cuts in the form of wavy lines
are made between the stamps and great care is
required in separating them. All these methods
were not successful and Europe in the
19th century. Asian countries,
however, used this system till as the
1960’s.
GUM This is the adhesive
substance usually applied on the back of stamps
for pasting them on letters. Occasionally stamps
are not gummed for various reasons. In the
nineteenth century tree gum was used which
cracked after a few months if not used. Cracking
also breaks the stamp itself. Often bacteria
consume the entire gum.
These days,
two types of gum are universally used. Polyvinyl
alcohol (PVA) is most common in Pakistan as well
as in other countries. It is somewhat glossy and
Colour-less, because of the presence of alcohol
in it, this kind of gum is being replaced with
Gum Arabic (GA) and the recent Pakistan stamps
are gummed with it. Gum Arabic also so
Colour-less that it cannot be distinguished if a
stamp is gummed. Since 1973, a substance called
dextrin is added to PVA. The mixture appears
bluish green and is called PVAD.