apparently it can be made as follows:
If you can’t find ferric ammonium sulfate (the green stuff, not the brown stuff) then you might be able to make it yourself.
- It would be 1 mole of ferric hydroxide to 0.65 mole of citric acid.
I’ve never done this, but it shouldn’t be too difficult – once you’ve got a suitable powdered form of ferric hydroxide (C.I. 77492, Pigment Yellow 42 as a food additive, perhaps even pulverized hematite if you’re really desperate) which might be just as much of a challenge…
characteristic/uv_sensitive