> Hello all,
> Ferric Ammonium Citrate (Green) 110 grains 7.1 gm
> Uranium Nitrate * 30 grains 2.37 gm
> Water 1 oz 28.4 ml
>
> Print to a faint image and develope in 5% potassiun ferricyanide
>
> * This should make the print glow in the dark, and with the end of the
> cold war it should also be quite plentiful!!
Well it would be nice if those uraniums come down in price. The last one I
bought was about 1980 (Aldrich) & the cost of $25 for 10 grams at the time
seemed excessive. Uranium toners for *silver* are reportedly not stable,
though I never did enough of them to tell for sure. I have seen a uranium
toner plus sulphide on a silver print that made a truly gorgeous fiery
red, but never found the formula. I was told, however, that it came from a
book called "The Boy's Book of Toning," in case someone has one lying
around.
> Catechu ?* 4 grains 0.26 gm
>
> Shake well and filter. Tone the washed print in this soln.
>
> Wot's this? I've checked in various upto date chemistry books (1896).No
> joy!
> Another one for the wizz kids at Aldrich perhaps Terry?
Page 95 of Encyclopedia of Photography, 1911. "An extract from the wood of
a species of acacia....used for toning platinum prints, also for toning
blue (ferro prussiate) prints to a greenish-black color." The next article
describes Catechu Toning for platinum prints.
A current version of catechu is, as I recall, available, under another
name (catechin?), in fact I'm pretty sure I have some. It's in some of the
early Dictionaries of Photography & if no one else posts it I'll look it
up.
> Soak print in in a 35% soln of Potassium Sulphocyanide( Potassium
> Thiocyanate?),
Yes.
Judy