Beautiful atomic blast test--when the French were testing their nuke capabilities. The Cyanotype* is printed on 140 lb Arches Watercolor paper and measures 22" x 30"

The cyanotype process was developed by scientist and astronomer John
Herschel in 1842. The process was created only three years after
photography was invented. This process instead of using silver like
typical photography uses iron. The iron ‘salt’ solutions are combined
and coated on watercolor paper in a dark room and allowed to dry. When
a negative or plant material is placed on the paper it becomes a film
negative. The uncovered areas are exposed to UV light and cause a
reaction to the iron solution reducing it chemically to a deep
Prussian blue. The print is then washed and the covered dark areas on
the negative create the white and the exposed become deep blue. It is
a simple and natural process.*