From: Sandy King (sanking@hubcap.clemson.edu)
Date: 08/05/00-07:59:10 PM Z
I have been printing with the Argyrotype Process of Mike Ware for the past
week or so and am very pleased with the results (and consistency) on
Fabrianto Artistico paper. The color of the prints, untoned, is a very
attractive dark brown and contrast can be changed by adjusting the amount
of Sulphamic Acid in the sensitizer. However, Argyrotype uses the much more
expensive Silver Oxide rather than Silver Nitrate. Mike describes a way to
precipitate Silver Oxide from Silver Nitrate, as follows:
"Alternatively, 7 g Silver(I) Oxide may be precipitated from a solution of
10.3 g Silver Nitrate by adding a solution of 2.5 g Sodium Hydroxide; after
filtration and washing, the moist precipitate may be dissolved in the
Sulphamic Acid."
I don't understand the concept of a chemical being "precipitated from"
another but I have on hand a large suppy of silve nitrate and would like to
give it a try. Can someone explain how I would do this in practice,
especially the part about filtering and washing?
Sandy King
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