Etching copper with ferric chloride

I asked some time ago about chemicals for etching I was using nitric
before and many folk recommended Ferric chloride and ferric nitrate
instead. I saved all the replies to use when I was feeling brave,
then just when I need the the hard drive on my computer
goes kaput.

The ferric chloride I bought is already a solution ay 50% and the
ferric nitrate is in crystal form at 98%. I have no idea of the
quantities of water to mix with them

I would be really grateful for any advice.



Just remember that Ferric chloride is used for copper, and the
Ferric nitrate for silver. Use the Ferric chloride as you already
it in solution form. No need to dilute.

Ferric nitrate is mixed with water until it is the color of strong
tea. I just pour out the amount of water I will be needing, then keep
adding the ferric nitrate until it gets to the color of strong tea.
If it seems to be too weak, I just add some more crystals.

You might check through the Orchid Archives as there is a wealth of
on using both of these etching mordants.

Alma Rands

Hi Jeanette



Karen Bahr - Karen’s Artworx
Calgary, Alberta, Canada

Hi Jeanette,

I do loads of etching and with the ferric nitrate crystals I’ve tried
various methods. I’ve found that the most foolproof way is to weigh
out equal quantities of water and crystals and then mix together. I
have also found that the plastic lunch boxes with a bendable clip
thing along each side is a brilliant way of storing the solution. I
just tape my piece of silver onto a piece of polystyrene ceiling
tile, float it face down in the tub and use a totally plastic kids
cheap paintbrush to gently ‘tickle’ the surface every few mins. It
works a treat… happy etching!

Sheffield UK


If you duct tape a small aquarium airation pump outside the plastic
bucket, you won’t need to “tickle” the etching process. The
vibration of the pump does the agitation for you. You can check back
in an hour or so.