Hi again Helen -
Thanks very much for the recommendation. I went to the website and
searched both ferric nitrate and iron nitrate and no results came
back - they seem to have decided they don't sell it today! ;-)
I don’t know whether you saw my earlier reply a few days ago now
about ferric nitrate here in the UK, but I’ve just checked with the
megauk.com site I suggested, searching for ferric nitrate, and up it
came - ferric nitrate etchant for silver, 1 litre, 17.50 GBP. Which,
as I say, is how I bought mine.
Again, I hope this helps.