Stone
lithography was the first printmaking technology that allowed
a traditional artist to work using traditional techniques, and
to create prints that could rival an original painting in terms
of detail, mood and color variations. Stone lithography was
extremely popular starting in the early 1800s, and even though
more modern methods have replaced the majority of its uses,
it is still practiced today by some artists and lithography
studios.
The
basic idea used in stone lithography is extremely simple:
1. The artist draws/paints on the stone with a greasy substance.
For example, a litho crayon is a soft waxy/greasy crayon. There
are also litho paints and pencils. The stone picks up this greasy
substance and holds it.
2. The stone is moistened with water. The parts of the stone
not protected by the greasy paint soak up the water.
3. Oil-based ink is rolled onto the stone. The greasy parts
of the stone pick up the ink, while the wet parts do not.
4. A piece of paper is pressed onto the stone, and the ink transfers
from the stone to the paper.
For
a wonderful article that shows step by step examples of the
process of stone lithography, see How
Stuff Works
Stone
lithography was used heavily during the early years of cinema.
Several changes to the lithography industry caused the elimination
of the use of this process.
Large
slabs of limestone had to be used which were extremely heavy
and bulky. The majority of these were imported from the Limestone
pits of Bavaria. The bombing of World War I destroyed a large
number of limestone pits, so an alternative had to be found
for a large number of lithographers.
Some
of the major lithographers turned to using a zinc plate instead
of the limestone from necessity. Even though it gave the final
image a slightly grainier look, it became the dominant printing
process in the U.S.
By
the late 30's, another major change was in the works with the
movement to offset presses. This process is VERY distinguishable
from the stone lithos.
Since
lithos using zinc plates were not marked any different, most
collectors consider these posters as stone lithos.