DIY silver recovery on the cheap

[BHuij]

I know this question has been asked before, so I'll try to be specific and provide all relevant details.

My goal here is to recover small quantities of silver from my B&W film and paper fixer (TF-5) to provide to my friend who casts semiprecious metals and creates custom jewelry, so he can make me a few pieces. To that end, I'm not terribly concerned with the economics, the efficiency, the purity of the final result, or anything like that. I just think it would be cool to wear a ring made out of silver from my own darkroom, and that would only take a few grams.

In my research so far, I stumbled on this article: http://analoguephotolab.com/silver-extraction-from-exhausted-film-fixer/

Makes it seem like it might be as simple as taking my exhausted TF-5, adjusting pH to 6 with some acid or (rather alkaline) tap water as needed, and tossing in some non-stainless steel wool for a few days. Then filter the liquid through coffee filters, let them dry, burn them, and hit the ash with a torch in a crucible to get at the metallic silver left behind. Possibly with some addition of borax and/or washing soda, though I'm unclear on what exactly those do to help the process along.

1. Has anyone tried this who can confirm it works (or definitely doesn't work)?
2. Is a regular propane torch hot enough to melt the metallic silver in the ash?
3. What grade of steel wool would work best?
4. How long should I expect to need to leave the wool in the fixer before it's diminishing returns on how much silver I recover?

 

[MarkS]

That's a lot of effort to gain what will likely be a very small weight of silver.

 

[BHuij]

I... yes. I'm aware of this.

 

[Dirb9]

Did that many years ago in high school, as the photography room was adjoining the jewellery metals area, and I thought it would be a fun experiment. Finer grade steel wool allows for more surface area exposed to the fix. I used 3 or 4 balls of steel wool in a gallon of fix, left it for about a week. A propane torch worked to get most of the steel wool burnt off, but I did end up needing to finish off with an oxy-acetylene torch. Oxy-propane may get you close enough, but I don't think a plain propane torch will get hot enough. Borax (flux) helps bring impurities out together so they can be burned off or removed as slag.

In that experiment, I recovered about 10 grams of silver. My teacher pointed out that I used probably about $5 of consumables to recover a couple bucks of silver. Fixer is considered exhausted anywhere between 2-10 grams/liter, depending on whether it's being used for color or b&w, paper or film, etc.