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Old 26th Jan 2020, 6:48 pm   #24
Graham G3ZVT
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Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,676
Default Re: Black oxide coating on brass

Quote:
Originally Posted by emeritus View Post
When I used to do my own black and white photography, I found that spillage of exhausted fixer would silver plate the pennies I used to use under the fixer dishes to level them up. The plating was initially black, but would readily buff up shiny using a cloth. I found it worked on the brass door knobs of our prefects' room. If
left the silver plating would soon blacken. Finding someone who still uses traditional processing that used fixer could be cadged from might be less difficult than trying to source toxic chemicals. The fixer should ideally be as exhausted as possible: fresh fixer contains no silver.
My dad and I kept our working strength chemicals in glass pop bottles, I don't think it occurred to either of us it wasn't the best idea. Anyway, Accutol & Accufix were expensive, so we kept the solutions as long as possible. I was interested in plating (electroplating) so I missed a trick there.
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