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Albumin Prints--Identification

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  • Albumin Prints--Identification

    Identifying the Albumin print with absolute certainty is, unfortunatly, a rather complicated process involving gross examination, microscopic examination, and various destructive tests only the safest of which will be described here. The need to absolutely and positively determine if a print is an Albumin type probably will never arise for the majority of us, so the following will focus on ways to determine the prints nature to a fairly high degree of certainty without going to extreme and costly measures.
    The first step in determining the nature of a print is to simply look at it.What we are looking for is (1) general color-what coloration is present. You will recall that the albumin prints tend to show a sepia or warm tone, and that because the binder in which the silver image is held is albumin which tends to yellow, Look at the highlights to see if yellowing is present. If so, that would begin to suggest this might be an albumin print. Next note the degree of fading, if any. Albumin prints,even with toner treatment tend to fade first in non image areas then overall. This, however is not specific to albumin photos but noting the fading will give you an idea of how the photo has been cared for and what preservation measures may be indicated-more about this in a later post.(2) Look for cracking of the image surface--Albumin print, if cracked will usually do so in a pattern resembling the texture of the skin on the back of your hand. Usually a magnifying glass can pick this up. (3) Attempt to date the photo-recall that from 1855 to as late as 1920 this process was in use although its hey-day was from around 1855 to 1895. Most of the Carte de visite( the forerunner of todays "wallet" sized photos) Cabinet card type photos (larger version of the preceeding),stereo view cards and misc mounted and some unmounted photos you see from this time period will be Albumin.
    Next to destructive testing, examination under a low power microscope provide the strongest evidence. Recall that the process of making an albumin print begins with soaking a sheet of fine rag paper in strong salt solution, drying, then "floating" it on a mixture of hens egg white to which has been added ammonium or sodium chloride and later citric acid (as a preservative). The albumin layer thus formed acts as a "layer" to hold the silver which will later produce the image, after being soaked in the silver nitrate solution to "sensitize" the paper. The Albumin layer is pretty much transparent and thin, thus, at magnifications of 30-40x the paper fibers are very visible, from highlight to dark areas. Later photo methods which involved the use of barium sulfate as a binder layer partially or completely obscure the fibers.(See Attachment) While there were collodian prints made without using the barium sulfate or baryta binder, they are somewhat rare, but because of a lack of a baryta layer fibers can be seen. More in a later post about the collodian and gelatin prints.
    There is one more way to identify the albumin print, but I strongly advise you to carefully consider if it is worth doing, and if you do, get the owners informed consent in writing. Also, do so at your own risk. I advise to skip it, but am presenting it here as an educational item only.
    A simple test involving the use of a very small amount of water and wood alcohol. The photo in question is placed on a flat well lit surface. A very small drop of water -AND I MEAN SMALL- is placed on a corner of the photo surface in a very out of the way location as in, close to the very edge of the paper. Allow the water droplet to sit undisturbed for 60 sec-{By The Clock}. Carefully blot up the water and examine the area with a magnifying glass. If the area under the droplet has swelled(best seen viewed at an angle) or cratered/dissolved, this is a gelatin print. Next, in the same area but far enough away to not confuse results, repeat this procedure with the alcohol. If the test surface dissolves, or becomes tacky this is a collodian print.
    So , here is what we have:Collodian is dissolved by alcohol. Not affected by water.
    Gelatin is affected by water but not by alcohol.
    Albumin is not affected by either.
    Thus, if after doing this the test areas show no change, its an Albumin print. Next post will be concerned with deterioration of albumin prints and preservation. Thanks Tom
    Last edited by thomasgeorge; 11-18-2001, 02:33 PM.

  • #2
    Well worth waiting for!

    You could write a book on this subject. You are that good at it. It is well presented in a way even the average layperson can understand and the examples you showed to support your subject were a good visual tool. All in all, an excellent presentation Tom. I enjoyed it imensely. As far as I'm concerned, you can keep them coming on up to present day photos. I'm eating this stuff up. (chemicals and all )
    DJ

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    • #3
      I'm in total agreement with Debbie. I think you are making available a valuable source of information. Thanks for the effort Tom.

      Ed

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      • #4
        Very informative Tom,well written and interesting as well. I'm looking forward to more of this kind of article,thanks for taking the time to enlighten us.

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