Old potassium dichromate

Discussion in 'Alternative Processes' started by mark, Jan 21, 2012.

  1. mark

    mark Member

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    I found 100g of Potassium Dichromate at the bottom of a box at the bottom of a pallet I bought at a school auction this morning. I would say it from the late 80s or early nineties.

    Would it still be good?

    There was also a lot of glass plates for holograms that said open under safe lights that were wide open. Those are shot. Anyone want some little glass plates?
     
  2. Hexavalent

    Hexavalent Subscriber

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    If it's still bright orange crystals, it's likely good. I had a jar on the shelf for 20+ years that was perfectly okay.
     
  3. John Austin

    John Austin Member

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    If it is still sealed

    If it is still sealed and as it was kept in the dark I can see no great chance that it will not be good - However, there is only one real test . . .
     
  4. mark

    mark Member

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    It is pink in color. Does that mean it is bad?
     
  5. cliveh

    cliveh Subscriber

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    Potassium dichromate is a nasty chemical (handle with care and read the health and safety instructions).
     
  6. railwayman3

    railwayman3 Member

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    Most references describe pot dichromate as being a bright orange-red color, which is how I would describe the product which I've used in the past.

    You really need a fresh sample to compare, as we all have different ideas of describing colors. But I wouldn't expect a "good" sample to be a "baby-pink" or similar shade of color?
     
  7. Hexavalent

    Hexavalent Subscriber

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  8. johnielvis

    johnielvis Member

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    100 grams...pink??? maybe it's just LABELLED at pot dichromate...even diluted with water i'ts always orange...VERY diluted it gets yellow----never heard of pink with this stuff....

    well--jsut mix up like 2 grams with some diluted sulphuric acid and see if it will clear a developed negative to cleaar film base..if so..it's what it says it is and it's good
     
  9. Hexavalent

    Hexavalent Subscriber

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    Please don't go adding sulphuric acid to things unless you are 110% certain of what you're dealing with.
     
  10. mark

    mark Member

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    I will look at it again tomorrow. It was in a milk white bottle.

    I ain't mixing a thing with sulfuric acid unless I am dead sure what it is. I've seen a guy after a chemical mishap.
     
  11. OzJohn

    OzJohn Member

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    I have a small brown bottle of it that would be close to 50 years old and the crystals are still orange. OzJohn
     
  12. mark

    mark Member

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    I opened the bottle and it seems to be the right color. I guess I am good to go.