For collectors of
Pre World War II paper material-- whether it's baseball
photographs, theatre programs,
movie posters or presidential prints-- there is a sophisticated yet
inexpensive and easy to use tool for quickly identifying many modern
reprints and fakes. This tool is
called an ultraviolet light or black light. While there are many uses for black
light in collecting and beyond, this chapter introduces on how it can
be used to identify modern paper and cardboard.
How Black Light Works
An ultraviolet light, or black light, allows the
examiner to see things not seen under normal daylight. Ultraviolet is outside the human’s
visible spectrum, meaning that it cannot be seen by human eyes. However, in an otherwise darkened
room, different materials can fluoresce (glow) under ultraviolet
light. Most of us have
experienced black lights that make the whites on our shirts or shoes
glow brightly. Some materials
fluoresce brightly, some not at all, and the rest somewhere in
between. Fluorescence can differ
in color. For example, some inks
fluoresce yellow, some brown and some
blue. This quality of
fluorescence happens at the atomic level of the material.
Identification of Modern
Papers Using Black Light
Ultraviolet light is effective in identifying of
many, though not all, modern paper stocks.
Starting in the
late 1940s, manufacturers of many products began adding `optical
brighteners' and other new chemicals to their products. Optical brighteners are invisible
dyes than fluoresce brightly under ultraviolet light. They were used to make products
appear brighter in normal daylight, which contains some ultraviolet
light. Optical brighteners were
added to laundry detergent and clothes to help drown out stains and to
give the often advertised `whiter than white whites.' Optical brighteners were added to
plastic toys to makes them brighter and more colorful. Paper manufacturers joined the act as
well, adding optical brighteners to many, though not all of their white
papers stocks.
A black light can identify many cards, posters and
other paper items that contain optical brighteners. In a darkened room optical
brighteners will usually fluoresce a very
bright light blue or bright white.
To find out what this looks like, just shine a recently made
white trading card or most types of today’s printing paper under a
black light.
If paper stock
fluoresces very bright as just described, it almost certainly was made
after the mid 1940s. It is
important to note that not all modern papers will fluoresce this way as
optical brighteners are not added to al modern paper stocks. For example, many modern news service
photos have no optical brighteners, This means that if a paper doesn't
fluoresce brightly this does not mean it is necessarily old. However, with very few exceptions, if
a paper object fluoresces this way, it could not have been made before
World War II. I would guess that
well over 90% of modern reprints and fakes of Pre World War II trading
cards and photographs contain optical brighteners that can be
identified with a black light.
Often times alterations
to photographs or prints can be detected with a black light. Alterations can include repairs with
glue or tape. Under black light
the different material will be obvious as it fluoresces differently
than the rest of the item.
Before declaring objects fakes and making a
citizen’s arrest on your grandmother, it is essential that the
collector gain practical experience.
This means using a black light to examine and compare the
fluorescence of a variety of items.
With photographs, make sure you shine the black light on all
sides and edges. This is because
the gelatin on the front of the paper often prevents the front from
fluorescing. The beginner
should also realize that while this is an effective tool for
identifying many fakes, it is only one of many tools and methods that
an expert uses in authentication and forgery detection.
The collector should also follow
all safety rules for the use of black lights. If used correctly, they are safe,
but, for example, the user should not look directly at the light. Boxed black lights should come with
directions.
Where to buy an
ultraviolet light
Black lights and ultraviolet lights are widely
available and have a wide variety of uses. Geologists use them to identify
rocks, collectors of glass uses them for authentication. They are even used to find scorpions
at night. Black lights are sold
by many science, hobby or rock stores.
I bought mine and tested it out at a hobby store in Seattle.
The
can also be purchased online. I
have seen hand-held models offered for well under $20 each on eBay and
Yahoo stores. Art & Collectors Reproduction
News recommends that the average collector buy a longwave black light as opposed to a shortwave
black light. Shortwave is
important in the examination of some stamps and other objects, but longwave is the safest yet still useful for most
collectors.
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