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where dose silver in fixer come from

rbrigham

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hi

Can anybody tell me where the silver in fixer comes from
is it in the paper or in the developer
dose the paper need to be developed
will there be more silver in the fixer if the print is mostly white or mostly black

I am looking at silver recovery and was wondering if it would be possible to extract
the silver from unwanted prints buy just leaving them in fixer

also can i mix old fixer and blix togeather

thanks

robin
 

nworth

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It's in the paper (or film). The fixer dissolves the undeveloped silver salts in the film or paper, making the image stable.
 

2F/2F

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Hi, Robin.

There is no silver in fresh fixer. The silver in used fixer has been pulled from the film or paper; the opposite of what gets developed gets fixed (meaning the silver gets removed), with film or paper.

Therefore, yes, there will be more silver pulled into the fixer with thin film or bright prints than with dark or average ones. (In the same way, thick film or dark prints eat up more of your developer than light or average ones.)

Paper and film do not need to be developed in order to be fixed. But they cannot be developed after they have been fixed. This is because fixing removes undeveloped silver. Therefore, if you fix before developing, all of the silver, exposed or not, is removed.

To get the silver from trash prints and test strips, you can soak them in a solution of potassium ferricyanide, and then fix them. The ferricyanide bleach changes already-developed silver so that it can removed by fixer (or redeveloped). If you do this with fiber paper, I suggest doing a full hypo clear and wash, and saving the blank paper. It is usually good quality paper that can be used for alternative processes, art projects, or just for scrap paper if nothing else.

I am not sure if you can send blix to a silver recovery place mixed in with the rest of your fixers. But things will be more efficient and economical if you use a separate bleach and fixer for your C-41 processing. Not only is this the "proper" intended color negative process, which will give you more stable negatives, but it also allows each chemical to last longer, to be used for less time when processing, and to be replenished/regenerated if you want. Raw chemicals in bulk are also much cheaper than blix kits.
 

Gerald C Koch

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Hi Robin,

Your question is a perfectly valid one although somewhat troubling. This is by no means a criticism, but I would suggest that you read up on the silver based photographic process. You do not have to be a chemist to understand what happens when film/paper is processed. This information may be helpful should other questions arise.
 

Juri

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This topic really makes me wonder how much silver I just pour down the drain.
 

removed account4

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hey robin

there was a thread about desilvering prints a little while ago
(there was a url link here which no longer exists)

the blix+fix have to be the right ph to use a trickle tank or silver magnet.
it needs to be about ph 3 to work right ...

(there was a url link here which no longer exists)

good luck !
john
 

wogster

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This topic really makes me wonder how much silver I just pour down the drain.

Actually you shouldn't just pour it down the drain, silver is toxic to the organisms that make your septic system or your towns sewage treatment plant operate. Spent fixershould be collected and taken to a Hazardous Household Waste treatment facility. Some towns have a permanent facility, some have special collections for it. If you know of a professional lab nearby, ask them if they use silver recovery, they may be willing to take it from you.
 

Gerald C Koch

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There are several ways to recover silver from spent fixer. The silver can be recovered by replacing it with another metal such as iron or aluminum. The silver can be removed as silver sulfide or reduced by the addition of sodium hydrosulfite. The cost of these supplies (metals or chemicals) reduces the profit. If the intent is to sell the silver and make the most profit one must uses electrodeposition. Here the main cost is the cost of the electricity. You would have to design your own system. There are available kits for home use but they cost almost as much as you would get for the silver recovered. As in any venture you must also consider how much your time is worth.

Silver recovery is discussed in Mason, "Photographic Processing Chemistry", Glafkides "Photographic Chemistry" and in many other texts.
 

removed account4

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hi jerry

i sell silver magnets ( small electrolytic units ) and they cost 45$ + shipping ...
with the spot price of silver is $35.665 / troy oz ..., ...
they require no assembly other than removing it from the box and plugging it in to a electrical outlet.

seeing the magnets can hold 30-32 troy oz, ... the refiners take 10%
( overhead/ refining fee ) the magnet hardly costs more than the profit from the silver recovered.

john