I am sorry I am not replying in the usual way as I am still trying to work out
how Compuserve 3 works. They are very proud of their new 'quote' facility but do
not include it in the obvious control button or drop down menus. If there is
anyone who knows ........
Thanks. When I spoke to Aldrich they did not know that it came in green !
My original supply, of which I have a few tubs left, is like pea flour. The
current supply is not so pure and has a black residue that does not usually get
in the way of producing kallitypes and cyanotypes. It just looks disgusting.
The impurities seem to vary so that some batches do the job and others do not
although the product appears the same to the naked eye.
Now I know how to make the ferric oxalate recipe work*, incidentally my stirring
rod assumed an interesting sculptural shape during the peroxide reaction the
other day, I want to have a go at making ferric ammonium citrate. to get
consistency.
Terry
* When the peroxide reaction stops and the mixture is still brown just keep
adding oxalic acid and the mixture will turn green and the precipitate wilkl
dissolve. Keep adding the acid untill the ferri reaction test works. The test
involves putting a series of drops of a 0.5 % ferri solution onto a plate and
then adding a drop of the green stuff to each ferri drop until the resulting two
combined drops of ferri and the green stuff go pale yellowy green rather than
blue.