aqua fortis

[varsity07840]

Is there a shelf life to aqua fortis?

[Pukka Bundook]

If it's kept out of the sun and cool, it seems to last for years and years. Might weaken a bit, but another coat makes up for that.
Just used some that must be getting on for 20 years old and it still worked.  Bit less bight maybe but it worked.  Been in a dark corner though.

[David R. Pennington]

I had some home made that was several years old that had seemed to lost it's strength. I didn't like the results and ended up making a new batch and starting over. I would test it first on some scrap or lacking that test in barrel channel before putting on stock.

[P.W.Berkuta]

I got about 1/2 qt. left that's about 15 years old that I keep tightly capped in a nalgene bottle in a draw. Still works maybe a bit slow just do two or three more coats

[hanshi]

Can it be easily reconstituted if it has weakened?

[rich pierce]

I’m not sure it weakens.  We are talking about home brew here, right?

[David R. Pennington]

Mine was several years old and just a little left in the bottom of the jar. My guess is mine had lost most of the nitric acid. I should have just went ahead and thrown it out. I used the rest of my acid to make a fresh batch, and it worked ok.

[smallpatch]

I have a batch of ferric nitrate, mixed 10 years ago, works just fine.
All the acid should be depleted from the get go.
As far as replenishing, not sure you have to.
Repeat after me.......ferric nitrate!

[hanshi]

I have a batch of ferric nitrate, mixed 10 years ago, works just fine.
All the acid should be depleted from the get go.
As far as replenishing, not sure you have to.
Repeat after me.......ferric nitrate!

"Ferric nitrate".