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  1. #11

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    When Jeffrey Mathias tested various batches of ferric oxalate in the 1990s he found that the B&S ferric oxalate was about 89-91% pure, the Artcraft FO 95% pure. See http://home.att.net/%7Ejeffrey.d.mat...e/contents.htm and in Chapter 6 click on Formulas for FO Sensitizer Solutions.

    This information may or may not pertain to current supplies. However, I obtain my FO from Artcraft and can state for a fact that in my work it has always been of consistently high quality.

    Sandy



    Quote Originally Posted by Kerik
    If you value your time, most definitely no, IMO. The quality of the B&S stuff is very good and it's very consistent. I've had mixed results with Artcraft's. B&S makes their's in-house, Artcraft is getting it from another supplier, I believe. I'm not knocking Artcraft, I'm a very happy customer of theirs. It's just that good, consistent FO is important if you want to make consistently good pt/pd prints. And compared to the other costs that go into making a print, the cost is negligible. For an 8x10 print that costs between $2 and $3 in materials, roughly 15 cents is in the ferric.

  2. #12
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    Quote Originally Posted by donbga
    Thanks Kerik. After mulling the whole thing over I agree making FO isn't worth the effort.

    Don
    Don, It is quite easy to make a liquid Ferric Oxalate. Dick Stevens's book on the Kallitype list three methods for making Ferric Oxalate. I have also included it in my book. The second method listed in Steven's is the way I make mine, and have been since 1994. The chemicals are not so hard to come by, but as you go up in volume, you really start to see a saving in price. I have it listed on my web site. I don't know if John meant to refer to me, or Eric Nelson ( I have not checked out Eric's site for some time). If you have l;imited lab ware, you may want to follow the other advice and just stay with B&S, but if you have any adventure in you, it takes some time as it does need to settle but it really is quite easy.

    Eric Neilsen

  3. #13
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    Quote Originally Posted by EricNeilsen
    Don, It is quite easy to make a liquid Ferric Oxalate. Dick Stevens's book on the Kallitype list three methods for making Ferric Oxalate. I have also included it in my book. The second method listed in Steven's is the way I make mine, and have been since 1994. The chemicals are not so hard to come by, but as you go up in volume, you really start to see a saving in price. I have it listed on my web site. I don't know if John meant to refer to me, or Eric Nelson ( I have not checked out Eric's site for some time). If you have l;imited lab ware, you may want to follow the other advice and just stay with B&S, but if you have any adventure in you, it takes some time as it does need to settle but it really is quite easy.

    Eric Neilsen
    Hi Eric,

    Wish I did have Steven's book as you know it is a rarity. I do have the facilities for making the FO, however as Kerik noted valuing ones time is a consideration. However the most important issue for me is how long the FO will stay useable and what % concentration would I have.

    Thanks,

    Don

  4. #14
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    Quote Originally Posted by donbga
    Hi Eric,

    Wish I did have Steven's book as you know it is a rarity. I do have the facilities for making the FO, however as Kerik noted valuing ones time is a consideration. However the most important issue for me is how long the FO will stay useable and what % concentration would I have.

    Thanks,

    Don
    I didn't know it was a rarity : ) I picked it up years ago at Photo Eye in Santa Fe when I lived in Taos and made regular trips to The PLatinum Gallery delivering work.

    Your materials will not change much over the time of making Ferric Oxalate. The only change will be to the H2O2 over time as it loses some of its strength. How much time is does it take? It is not a process that takes alot of time of active participation but periods of letting it sit. There are two steps that require a little real time; 1) measuring the chemicals, 2) achieving a finished solution. If you make good notes, like you were taught in basic chemistry, your solution will pretty be the same batch to batch. It may not be the same as BA&SA, Formulary or Artcraft but that does not make it bad, but rather it makes it your solution. What makes it bad is ferrous ions running around. How do you stop that from happening? keep extra oxalic acid in solution.

    What are you going to use it for? the requirements for ferric can be slightly different for different processes. If you can make your own ferric oxalate, and your own potassium oxalate, you free yourself up from a supply chain. You gain more control over your process and have more money to spend on silver, platinum and palladium or gold.

    For an investment of $180.00 you can make 2.5 liters of liquid ferric oxalate. I can forward to you a method of making it or you can go to the site that Sandy posted for Jeffrey and download how to make powdered.

    Many years ago I got in a discussion with Dick Sullivan about his ferric powder on the Alt photo list. I had used B&S ferric since 1983 after Tom Millea stopped making a liquid for us. I have known Dick for a long time.
    Experiments were being done by my ex business partner John Rudiak and David Michel Kennedy to try and improve BA&S powder or at least make it in line with the conversation.

    AS part of making ferric oxalate, one converts ferrous to ferric. If you can do this during the process of making it, you can surely do it to stuff you already have. You can't stave off the process for ever though. Sandy was going to try and freeze some. He may be getting ready to thaw it?

    Life is as consistent as you make it. Ferric oxalate is easy and cheap to make. And while as Mike Ware describes it as ill defined, it still works and has worked for a long time.

    Concentration of your liquid can be best estimated by specific gravity. In Stevens book there is a neat chart that the University of Notre Dame Science department whipped up for him. Is it definitive? Well no, but short of anything else it is a bench mark that I have used for 12+ years and it hasn't failed me.

    In the life time of print making, what are a few hours? if you have the lab ware and can get the H2O2, I can sell you a small amount of AFS- Ammonium Ferrous Sulfate and if needed Oxalic acid, and you can then see for yourself. The best judge of how something will work for you, is YOU.

    Eric

  5. #15
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    Quote Originally Posted by EricNeilsen
    I didn't know it was a rarity : ) I picked it up years ago at Photo Eye in Santa Fe when I lived in Taos and made regular trips to The PLatinum Gallery delivering work.
    The last I checked abe books had a copy for $235! More than I wish to pay.

    Quote Originally Posted by EricNeilsen
    What are you going to use it for? the requirements for ferric can be slightly different for different processes.
    Kallitype and palladium printing.

    Quote Originally Posted by EricNeilsen
    and your own potassium oxalate,
    Done that and it wasn't difficult just a bit messy. Making several gallons during one session wasn't that time consuming.

    Quote Originally Posted by EricNeilsen
    For an investment of $180.00 you can make 2.5 liters of liquid ferric oxalate. I can forward to you a method of making it or you can go to the site that Sandy posted for Jeffrey and download how to make powdered.
    Sure send it to me.

    Quote Originally Posted by EricNeilsen
    AS part of making ferric oxalate, one converts ferrous to ferric. If you can do this during the process of making it, you can surely do it to stuff you already have. You can't stave off the process for ever though. Sandy was going to try and freeze some. He may be getting ready to thaw it?
    I think he will thaw it out this summer. As an experiment I've frozen some as well.

    Quote Originally Posted by EricNeilsen
    Concentration of your liquid can be best estimated by specific gravity. In Stevens book there is a neat chart that the University of Notre Dame Science department whipped up for him. Is it definitive? Well no, but short of anything else it is a bench mark that I have used for 12+ years and it hasn't failed me.
    I suppose I could make a batch from powder and then measure the SG as a reference.

    Quote Originally Posted by EricNeilsen
    In the life time of print making, what are a few hours? if you have the lab ware and can get the H2O2, I can sell you a small amount of AFS- Ammonium Ferrous Sulfate and if needed Oxalic acid, and you can then see for yourself. The best judge of how something will work for you, is YOU.
    I've not been able to locate the bomb grade H202 and frankly I'm a bit leary of keeping the stuff around. As for the AFS I may be interested in getting some from you if I can't locate a source. I've got plenty of oxalic acid.

    Thanks for taking the time to discuss the procedure. I do like to save money and not paying 50 cents a gram for FO would be nice.

    Don

  6. #16
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    Quote Originally Posted by donbga
    The last I checked abe books had a copy for $235! More than I wish to pay.



    Kallitype and palladium printing.



    Done that and it wasn't difficult just a bit messy. Making several gallons during one session wasn't that time consuming.

    And I but my potaasium carbonate and oxalic acid in 50 lb bags , both only costing around 65.00, so for that little investment, I can make 25 gallons of developer. Quite a saving over what B&S sells potassium oxalate for.

    Sure send it to me.



    I think he will thaw it out this summer. As an experiment I've frozen some as well.



    I suppose I could make a batch from powder and then measure the SG as a reference.



    I've not been able to locate the bomb grade H202 and frankly I'm a bit leary of keeping the stuff around. As for the AFS I may be interested in getting some from you if I can't locate a source. I've got plenty of oxalic acid.

    I have had no problem with it. I don't have animals or children in my darkroom as it is a separate building in an commercial / industrial space.

    Thanks for taking the time to discuss the procedure. I do like to save money and not paying 50 cents a gram for FO would be nice.



    Don
    WOW!

    pH and excessive amounts of oxalate will be a concern. pH will effect color of your print. The excessive oxalate can be taken care of with a little ferric nitrate.


    Remember that what you will be measuring is the Sp Gr of that particular ferric oxalate powder mix! It may contain excess edta, ferric nitrate ( B&S did add small amounts) Look for purple crystals. Add you should add some oxalic acid to get the pH set up to help dissolve the ferric powder.



    I have had no problem with it. I don't have animals or children in my darkroom as it is a separate building in an commercial / industrial space.


    I bought my last batch of AFS through Johnson Mathey, 2.5kg. Last I looked at big bags 25kg it was only a bit more. The first time I bought it I picked up 500g for $50+/-.


    Recently sent some off to some one as a kit; without the H2O2. Check with local hair dressers. Bryant Labs out in Berkely was one source that I used and since they have exited the alt world, I would check with Mike at Artcraft. 1 pint will do quite a bit but the cost of getting a gallon is not 4X but only 1.3X or something like that.

  7. #17

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    Notes on how -not- to test ferric oxalate purity.

    Quote Originally Posted by sanking
    When Jeffrey Mathias tested various batches of ferric oxalate in the 1990s he found that the B&S ferric oxalate was about 89-91% pure, the Artcraft FO 95% pure. See http://home.att.net/%7Ejeffrey.d.mat...e/contents.htm and in Chapter 6 click on Formulas for FO Sensitizer Solutions.

    This information may or may not pertain to current supplies. However, I obtain my FO from Artcraft and can state for a fact that in my work it has always been of consistently high quality.

    Sandy
    Hi Everyone,

    Kevin Sullivan here, from Bostick & Sullivan. I generally try to stay above the fray and refrain from comments. But this thread bugs me because of the general lack of understanding about ferric oxalate as a chemical, and the false info being propagated.

    This pertains particularly to Jeffrey Mathias' well intentioned, but completely off base testing of ferric oxalate purity. His test is significantly flawed. His methodology is permanently crippled. Yet it looks sophisticated enough to fool some folks. This is very bad science.

    Ferric oxalate is a non-stoichiometric compound, meaning that the molecular structure is undefined. Think of ferric oxalate as a three armed octopus with a suction cup at the end of each arm. When you make a batch of FO, these octopi arms can stick together in any combination and size. They can stick to each other, they can stick to other FO molecules, or they can be free floating. This will effect the size and shape of the molecules, but notice that it is all still 100% FO no matter how jumbled and dense their structure becomes.

    This is what Dr Mike Ware means when he says FO is an ill defined compound, it has no regular shape and size to its structure, it is entirely random.

    Stoichiometric compounds are things we are commonly familiar with that have a fixed atomic structure and relationship to themselves. Sodium chloride, potassium dichromate, and most familiar chemicals are stoichiometric. They just don't have multiple sticky arms that can link in an infinite variety of ways. So their density stays stable because they can only interact in limited, known ways. If you took 10g pure sodium chloride and dissolved it in 100ml water, the specific gravity would be readily predictable, and any extra contamination or impurities would shift this specific gravity measurement.

    Unfortunately, we don't know at any given time how the FO has decided to array itself.

    For a simplistic analogy, picture each FO basic unit as a strip of velcro. We fill up two buckets with velcro strips. I reach into one bucket and pull out a single strip of velcro and it weighs 50g. Jeffrey Mathias reaches into a second bucket and pulls out a giant wad of velcro strips all stuck together in a ball. His lump weighs 500g. Jeffrey then ratios the weight of my velcro to the weight of his velcro and determines "Kevin's velcro is only 10% velcro, where as my lump is true 100% velcro." When, to any objective observer both pieces are 100% pure velcro, just different sized clumps.

    The math that Mathias relies upon only works with stoichiometric (fixed) compounds. If you were doing this test with a dichromate, then it would be a valid measure of purity. His testing is meaningless to non-stoichiometric materials.

    To jump into Sandy King's world, let's look at gelatin for a second. Gelatin is also capable of chaining together into bigger or smaller molecules, often measured as bloom (hardness). So, what's purer, 100% pure 75 bloom gelatin or 100% pure 250 bloom gelatin? If you use Jeffrey's methodology you will calculate out that 75 bloom gelatin is only ~25% pure/ 75% contamination, if based on the density of 250 bloom gelatin. We can immediately see how phoney that is.

    The major flaw is that specific gravity is not an indicator of purity for these materials. It just won't work that way. You can't even use it as a relative measure, i.e. "this FO is purer that that FO based on specific gravity...."

    So we have a guy (JM) who has a limited understanding of what he's measuring running around making claims like "B&S FO is only 91% pure" and confusing a couple of folks with his elaborate charts and graphs and math. Clearly he's confused himself. He makes statements like 'All weight measured to within 0.01 grams." in an attempt to bolster his claims of precision. Sorry, but no matter how accurately you weigh your samples, you have an inherently flawed result which proves nothing about purity.

    Folks make much ado about Dick Stevens' measurement of specific gravity from the Kallitype book, and use it as a baseline comparison for measuring other FOs. But the specific gravity of Dick Stevens' FO is again a red herring. It tells us nothing about the purity, even if we assume Stevens made absolutely perfect 100% pure FO, his specific gravity is not a useful number for comparing against other FOs as a determination of purity. Again, this would work with a stoichiometric compound but not FO.

    Mathias has several other tests in his chapter, all equally as flawed. His determination of purity based on dissolving time for the two powders is so obviously wrong I'll only mention it in passing. His other major test is an "optimized" printing eyeball observation test, this test is just plain silly. I could write several more pages about this but suffice it to say they have holes in the methodology so large I could park the goodyear blimp inside the empty spaces.

    I hope that this straightens out some of the misperceptions about FO and its purity.

    Also, Eric Neilsen casually throws out the idea that John Rudiak and David Michael Kennedy somehow struggled to improve the quality of B&S ferric oxalate, all to no avail. This is because DMK and Rudiak also misunderstood the very nature of FO. They confused the use of oxalic acid in manufacturing the FO, with the addition of oxalic acid to pure FO when mixing it for use in printing.

    As many people have noted, adding oxalic acid to FO solution turns the solution from a dusty yellow brown color to a bright translucent green. Rudiak and DMK believed that they were neutralizing excess ferric nitrate with the addition of oxalic acid, and that "pure" FO would be a vivid lime green color. They were wrong. Pure FO powder is the familiar yellow brown dust. Adding oxalic acid to the FO powder starts to stoichiometricize the material, and it becomes greener with the addition of extra "impurities", in this case oxalic acid. We told them add as much oxalic acid as they like if it seems to help their particular printing style, but we weren't going to make "bad" FO just because they didn't understand the chemistry. Rudiak eventually got it, as he had a degree in chemistry from RISD. I have no idea what Kennedy thinks, he was never very technical and Rudiak was the brains in this situation. But I don't think it excuses Eric Neilsen from posting third-hand misinformation which slights B&S without telling the whole truth.

    In closing, I'd like to say that I have spoken with Jeffrey Mathias by telephone and explained to him the flaws of his study. At times he was speechless and could offer -no- valid defense of his techniques (especially his "optimized" print test). He has not corrected the major problems with his study even though they are quite obvious, once understood. So Jeffrey, for all his bluster about science, is not a scientist. A true scientist would acknowledge the flaws of his study and post information about the evidence that might disprove his research. Instead he hides behind a wall of complicated but useless mathemetics, hoping to fool a few more unsuspecting chumps into drinking his particular flavor of poison kool-aid.

    Jeffrey lists on his website several empirical tests for determining the purity of FO (using silver nitrate and pot. ferricyanide, for instance.) He readily admitted to me that B&S FO powder will easily pass all of those standard tests showing a high level of purity. When asked how, then, that the B&S powder passes all easily observable traditional tests of purity, yet we end up only ~90% pure in his crackpot specific gravity test, Jeffrey claimed that Bostick & Sullivan must have an unknown, untraceable impurity which we can mask so that it doesn't show up in his tests. Yes, seriously, according to Mathias, B&S has a special "stealth" chemical we use to cut the FO that is untraceable by modern science.

    B&S has spent 25+ years refining our ferric oxalate manufacturing technique, including quite a few unique, unpublished, methods for guaranteeing absolute purity. We are quite happy with the results and our customers get great prints. I'm sure that the materials provided by Artcraft and PhotoFormulary are also quite acceptable and make fine prints. But I'm not going to sit around and let a bunch of bad scientists with bad technique tell me that our fine product is 10% contaminated. These folks are either grossly uninformed or intentionally misleading people.

    Sorry for the long rant. Thanks for your time.

    Kevin Sullivan
    Bostick & Sullivan, Inc.

  8. #18
    Ole
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    It's a safe bet that any chemical containing trivalent iron ("ferric") is non-stoichiometric. Even something as simple and common as rust varies wildly! Add oxalic acid to that, and you don't have to be a particularly bright scientist to guess that it's going to be diffcult to quantify "purity": The oxalic anion is a very strong chelating agent, and will cling to anything in just about any possible configuration.

    Which got me to thinking: Oxalic acid is used as a rust remover in several different applications. Could ferri oxalate solution be made by dissolving rust (or a "purer" FeO(OH)*nH2O in oxalic acid? A small addition of dilute hydrogen peroxide to assore the oxidation state of the iron might be a good idea, but at least it would avoid a whole lot of tricky process steps and explosive chemicals?
    -- Ole Tjugen, Luddite Elitist
    Norway

  9. #19
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    Making Ferric Oxalate

    "Many years ago I got in a discussion with Dick Sullivan about his ferric powder on the Alt photo list. I had used B&S ferric since 1983 after Tom Millea stopped making a liquid for us. I have known Dick for a long time.
    Experiments were being done by my ex business partner John Rudiak and David Michael Kennedy to try and improve BA&S powder or at least make it in line with the conversation. "

    That conversation if I recall correctly, was about solution strength and the addition of EDTA tetra sodium and oxalic acid. If you have a powder of an ill defined substance, the best you can hope to claim, is that if you mix this powder at this concentration than you can have a % based solution of this powder; not of the pure substance at the base of the solution. The addition of Ferric Nitrate, little purple crystals, EDIT tetra sodium, and any other solid will be a part of the solid put into solution. Do they aide in the uniformity of the solution? perhaps. do they convert ferrous to ferric? They are part of the "whole" and that whole gives you a Sp Gr for your solution and by weight/volume a solution %.

    The conversation that I refer to was one that took place on the Alt Photo Process list over 12 years ago. The conversation as best as I recall was about making ferric oxalate and % of ferric, and many issues.

    I don't belive that I, Dick Stevens, or anyone else has said that using Sp Gar is a way to measure the absolute purity of Ferric Oxalate and I find it hard to believe that anyone would. What is being promoted is that a strong correlation exist between Sp Gr and active ferric oxalate. There is no doubt that solutions that I have made and those that were tested by the chemistry department at Notre Dame University for Dick Stevens show this correlation.

    Ferric Oxalate has been referred to as an "ill defined" substance by Mike Ware. I think that most people would agree. That being said, does it really matter? If you follow the say procedures, time after time, and the results can be duplicated both in practical senses of Sp Gr and in print speed and color, then what does it really matter? Bad science is bad science and sloppy lab work, will produce inconstant results.

    It should be obvious to all that this is a touchy spot with B&SA. I did not imply that Rudiak and Kennedy struggled those were Kevins words.

    "But I don't think it excuses Eric Nelsen from posting third-hand misinformation which slights BA&S without telling the whole truth." again kevins words... I refer to events that happened in the first person. Kevin if you have a problem with my recollection, send these people a link to the original conversation. What went on between you, your father, John and Michael was of course not in my view.

    And as I said before, "Concentration of your liquid can be best estimated by specific gravity". You can then test it by making a print.

    I have not used B&S ferric since 1994, I make no claims to it's purity. The question was, Can you make ferric oxalate either as a powder or liquid? Yes to both. Can you make it economically? yes. Better yet, once you can, you can rely on yourself to make prints with one less middle man.

    I am not in the business of selling alt process chemistry as my main endeavor, but I will not have my name dragged through the BS of B&S marketing. Because I stand up for alternative sources for information, chemistry and methods not being sold through the B&S pipe line does not give the good people at B&S the right the suggest I practice bad science.

    with all due respect,

    Eric Neilsen

  10. #20
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    "We told them add as much oxalic acid as they like if it seems to help their particular printing style, but we weren't going to make "bad" FO just because they didn't understand the chemistry. Rudiak eventually got it, as he had a degree in chemistry from RISD."

    It should be noted that John's chemistry degree did not come from RISD, an art school, but rather a college in Pennsylvania , Lebonan Valley College.

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