How do you remove silver nitrate stains?

[Doremus Scudder]

Hypo did not work. Bleach however took care of it after an overnight soak.

As mentioned, you should use fixer to remove the now-invisible stain after bleaching or it will come back.

Best,

Doremus

[Two23]

Now that we have a thread started and the OP answered, I'll add a little. Last month I was removing my trays etc. from the portable dark lab in the back of my Subaru after shooting wet plate. I had one of the trays full of water and a lot had sloshed out into the plastic storage box I used as the base of my dark lab. I was tired and thought, "Just water." I dumped it out on the ground. A few days passed but then one morning I looked and there was a big brown spot! The previous days had been heavy overcast but now it was sunny. Uh oh, wife isn't going to be happy. So I've washed it with a power washer, poured hypo on it and let it sit and then washed again, tried 50/50 ammonia and hydrogen peroxide. All of that lightened it but it's still there. It has a bit of a silvery sheen to it now. Should I try chlorine bleach, wash, and then high strength hypo again? My thinking is it's down into the pores of the concrete. Might get rid of some of it with a wire brush.


Kent in SD

[koraks]

It's likely the most valuable concrete slab out there, it being silver plated and all. I'd leave it as it is.

[robshepherd]

Doremus, I did just that. Look ma, no more stain! Thanks, Rob