</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (OleTj @ Mar 17 2003, 01:46 PM)</td></tr><tr><td id='QUOTE'> I can't believe I forgot that!
So far, I do van Dyke.
I also do salt prints, but my silver nitrate is at least the right chemical...
I intend to try Pd sometime in the future, I even have the Palladium already. I also have a 5x7 neg I think will look good in (cyanotype) blue.
But for the moment, my main concern is van Dyke - thus the ammoniumferricitrate.
As I mentioned, I have a degree in chemistry so making a ferrioxalate solution should be no problem. But the ammoniumferricitrate is a very poorly defined chemical with variable composition - besides, the only specifications I can find for "The good stuff" is "green". I can't synthesize "green"!
Ole </td></tr></table><span class='postcolor'>
Ah, if you have to have ammonium ferric citrate I would expose for 1/3 less than the higer purity. OTOH I use ferric oxalate to print Kallitypes and it works great. I would suggest you use ferric oxalate. As you know none of these light sensitve chemicals are very stable and I think AFC is less stable than FO. I order mine from B&S and the powder form lasts a long time. Of course making your own is ok, but IMO why hassle with it? If the order of FO plus shipping is less than the time and expenditure you would have if you do it yourself why not go with B&S or Artcraft, they will ship to you and when I used artcraft in the mail, with the famous burro it only took 2 weeks.
BTW if you want formulas for making Ferric oxalate let me know and I will post them here or send you the URL for the web site who publishes them.