TurkoTek Discussion Boards

Subject  :  Paul Mushak's comments
Author  :  Wendel Swan mailto:%20wdswan@erols.com
Date  :  11-15-2000 on 04:20 p.m.
Dear all,

Please forgive this long post, but I wanted to share some information that ought to be meaningful to parts of this salon.

The issue of the capacity of natural dyes to bleed continues to be discussed, with conclusions seemingly being drawn from anecdotal testimony. If we had before us an actual example of a rug with bleeding, simple dye testing could tell us whether the running was from natural or synthetic dyes.

While I can provide no personal expertise myself, in an earlier salon I cited an experienced local weaver and dyer to the effect that natural dyes in wool essentially do not bleed. I may have perpetuated a possibly incorrect belief by quoting Elena Tsareva as saying that she had "heard" that the excessive use of cochineal in the dye vat can result in bleeding, even though she was merely repeating something she had been told but had no personal experience with this effect.

Because of the continuing controversy, I asked Paul Mushak, a North Carolina physician and toxicologist as well as a recognized authority on the subject of dyes, for his comment. Here is his reply, without my further comment:

"Dear Wendel:

I have a few comments and conclusions in response to your e-mail query about the problem of whether natural dyes would ever bleed into adjacent areas of oriental rugs, trappings, etc. You may pass along these comments to whomever or in whatever venue where they may be useful. I have been occasionally tempted to write on the topic but I am always pushed for time with my regular professional work. I have not considered any formal write-up paper or the on-line version of ORR.

Context and Historical Comments

There has been considerable confusion about the matter of whether natural dyes will or will not "bleed" into adjacent areas, bleeding being most discernible and most objectionable as to aesthetic appearance of a piece when bleeding is to ivory or other light color areas. Bleeding has also been claimed as a crude visual criterion for sorting out natural from synthetic dyes. To be more technically precise, however, this sorting out would have to include both natural AND FAST CHROME DYES as non-bleeders and potential bleeders as synthetics which are not chrome-mordanted. That is, natural and chrome-mordanted dyes on wool in rugs would not bleed, while synthetics other than chromes would bleed. However, absence of bleeding is, obviously, not evidence of natural dyes being present. Pieces may simply contain dyes that would run if given the chance but were never washed or otherwise made damp, i.e., not given the chance. I have seen numerous cases of easy-to-bleed red synthetics in the more recent Turkmen rugs, specifically the Afghan "Mauri" or "Sarooq" pieces from the late 1960s and 1970s, but where the whites and creams are crisp and no bleeding has occurred simply because the rugs were never washed or ever became damp. These pieces therefore seem O.K. Taking a damp cloth to any red area in these pieces, sad to say, gives immediate running with even gentle rubbing.

This confusion over whether natural dyes will run onto adjacent areas traces, at least in part, to the appearance of an off-color in the cream/ivory portions of Turkmen pieces otherwise assumed to be of considerable age. In some cases, the off-color appearance approaches a discernible tan-pink. This was the focus of Steven Price's letter in HALI. Also, certain very fine and presumably early dozars from the Fereghan (Zili-Sultans) and Malayer Hamadan (Mishan Malayer) areas carry an apparent early synthetic red that has typically bled. Similarly, there's a type of Senneh kilim with a garish red and grey-olive palette with this run problem. Here, too, the red appears to the eye as early synthetic since the pieces seem to be from the early 1900s.

A seemingly well-known example of the problem in Turkmen work is a rare example of white-ground asmalyks, i.e., the allover flower heads in a field of ivory and a simple border, sold by Sotheby's in the early 1980s for 44K (a record at the time for Turkmens), and mentioned again in print more recently. It had a pink cast in the ivory. That led one Turkmen "expert" to reputedly postulate that the pink was (presumably natural) field yarn ivory but dyed pale pink to symbolize the bleeding attending loss of virginity during the honeymoon by the bride. This would serve as proof of a bona-fide virginal status to the newly-minted husband. Sheesh! It's hard to envision any likely situation where this explanation would apply. In theory, the virginal bride in the wedding camel cupola and on the way to her wedding would not use a camel festooned with flanking asmalyks already showing symbolic evidence of activity before the honeymoon. This howler shows what people will say to defend forking over big bucks for a rare asmalyk with what probably is an early synthetic dye.

I can offer a number of conclusions on the topic, based on available scientific evidence and historical information.

Conclusion 1. Naturally dyed wool yarns in any rug-producing tradition and area would simply not bleed as a general rule. Nor would modest or moderate bleeding occur into undyed or lightly-dyed adjacent areas.

Dyeing of yarns with natural dyes for rugs and trappings in the Middle and Near East entailed natural dyes being applied to wool (or in some cases silk) yarns which had first been heavily mordanted by any one of a small group of metal mordants (sometimes with minor use of additional fixatives but never without metals as main mordant). The metal mordant worked by binding first with the wool during mordanting, and then connecting the wool surface with the dye through further binding when placed in the dye bath.

A metal atom functioning as a mordant forms a binding "bridge" between the dye molecule and binding sites on the wool surface. That is, we have a metal mordant atom in the middle, between a fiber-mordant binding surface on one side and dye-mordant binding sites on the other. Each mordant atom has multiple binding sites, some of which hook into the fiber surface, the rest hooking onto the dye. The dye can't release from this binding bridge because it's held tight by binding with the mordant metal atom. Normal washing and use of rugs and trappings would not release the dye molecule from its binding with, say, aluminum ion in the case of alum mordanting. In fact, dye release from testing fibers in the lab requires use of strong lab chemicals such as acids to liberate the dye for subsequent analysis.

Conclusion 2. Overdying with more dye than mordant to accept the dye would not occur. It is rarely the case that one can overwhelm or saturate the metal binding surfaces with too much dye. Despite talk of too much dye in proportion to mordant being possible, giving free dye to bleed to adjacent areas, this rarely if ever technically happens. This is for several simple technical reasons. First, because the amounts of metal mordant used were huge. Any American craft dyer working, say, with alum (potassium aluminum sulfate) as mordant and natural dye baths can tell you this. Specialized dyers in rug areas would mordant the yarn, wash the mordanted yarn and then add the yarn to the dye bath. No free mordant existed at this point. Dyed yarns were typically then washed. Mordants were not typically applied in rug areas in the same bath for yarn as the dyes. Secondly, any excess dye in a bath would simply not stick to yarn at all, never mind hanging around to then bleed later, or would be rinsed off in the yarn rinse step. It would logically bleed off into the original water dye bath or the rinse water. This simple bit of logic has usually been lost on the scientifically naive.

Conclusion 3. Dyeing of yarns during the pre-synthetic period was a highly-specialized craft practiced by specialists. It was also a highly-developed craft in rug-producing tribal and village areas. Dyeing was never practiced by just anyone who tried their hand at it while also making rugs or trappings. Villagers and nomads typically bought or bartered for the yarn from the skilled dyers. One cannot argue that natural dyes would bleed if the process was done by unskilled or amateurish dyers.

Conclusion 4. Once a rug was made, it is unlikely dyes might bleed if the rugs or dyed areas got wet and stayed damp for a while. That occurrence would require migration of dye and mordant complex from one area of yarn surface binding to another. It would be highly unlikely. Secondly, the types of pieces showing dye running are usually those from arid areas, e.g., Turkmen, Central Asian pieces, not those from damp ones.

Conclusion 5. People here in the States who are proficient craft dyers and quite familiar with traditional dyeing in the major rug-producing areas should be able to readily show the above experimentally for one and all. For example, if yarn skeins are unmordanted, does any dye uptake at all occur when these are immersed in, say, a madder bath? If unmordanted yarn skeins can be discolored without mordants present, does the discoloration readily wash off with rinsing, as might occur with typical dyed yarn processing back in early times in Central Asia and elsewhere?

Hope the above is helpful.

Best regards,

Paul Mushak"

Subject  :  Re:Paul Mushak's comments
Author  :  Steve Price mailto:%20sprice@hsc.vcu.edu
Date  :  11-15-2000 on 06:55 p.m.
Dear Wendel,

I'm extremely glad to have the input of someone with Paul Mushak's knowledge of this subject. It does clarify a lot of points, and he is a genuine authority.

I am left with a few questions.
1. Marvin Amstey witnessed red running in an old Turkmen piece washed with boiling water. Did the boiling water make a natural dye run, or would the conclusion be that the rug really wasn't so old and the dye was synthetic?
2. What is the origin of the tan-to-red "off color" in what appear to be very old Turkmen pieces in various collections? It isn't clear from his words on that whether he believes that the pieces really aren't as old as we think or that the off color is not a dye run at all.

One interesting twist here is that while half the world is looking to C-14 and claiming that many Turkmen rugs are much older than we thought, the dye observations suggest that many are much younger than we thought. Maybe what we thought really is meaningless altogether.

Please extend my thanks to Paul Mushak for his contribution.


Steve Price

Subject  :  Re:Paul Mushak's comments
Author  :  Marvin Amstey mailto:%20mamstey1@rochester.rr.com
Date  :  11-15-2000 on 08:35 p.m.
Dear Steve,
The rug was an 18th-early 19th c C-gul yomut with a bad urine stain. The arrogant amateur poured boiling water over and through the rug where the stain resided. He was rewarded with about 40% stain removal and some ground color that ran.
Best regards,

Subject  :  Re:Paul Mushak's comments
Author  :  Wendel Swan mailto:%20wdswan@erols.com
Date  :  11-15-2000 on 10:11 p.m.
Dear Steve and Marvin,

The tale of someone using boiling water in an attempt to "remove" a urine stain begins to explain the color run. Hot, even boiling, water alone seemed an unlikely explanation to me since the traditional recipe for fixing dyes includes a lengthy steeping of the wool at or just below the boiling point. While it might not do the wool and the appearance of the finished rug any good, hot water should not reverse the process it was originally used to facilitate.

I am unable to explain it, but my understanding and observation has always been that urine causes a permanent chemical change in the colors in rugs. Its effect is not like spilling coffee, which can be washed out.

As to the effect of the urine on the dyes, recall that Paul said "dye release from testing fibers in the lab requires use of strong lab chemicals such as acids to liberate the dye for subsequent analysis." Perhaps the uric acid is sufficient to release some of the color, which then might run when water is applied. Someone else would have to say if that is possible. I can't. However, I can't recall ever seeing color run in association with urine stains, so it may be that the urine only changes the color but doesn't release it.

I certainly accept Marvin's age estimate of age, but we are once again left to speculate as to what other conditions might have existed for the running to occur. Could it be, for instance, that someone had tried to touch up the stained areas and the water (whether it was boiling or not) caused the touch up paint to bleed? Could there have been other contaminants?

The difficulty is that these analyses are case specific. Even a trained observer like Marvin might not have known of some condition of the rug that caused the running.

On Steve's second point, I have no idea about the tan-to-red "off color."

As to the age question, I wonder whether any general conclusions can be drawn. Dye testing, unlike C-14, is inexpensive and can be done almost anywhere. Yet few people ever bother to perform this simple test. I'll be the first to admit that I never have.



Subject  :  Re:Paul Mushak's comments
Author  :  Steve Price mailto:%20sprice@hsc.vcu.edu
Date  :  11-16-2000 on 06:46 a.m.
Dear Wendel,

I had thoughts similar to yours. That is, I believe that Marvin's judgment of the age of the piece he saw washed with boiling water is accurate, and I believe that he saw colors running. Like you, I wonder whether those colors were the rug's dyes or something else.

One rule of thumb (somebody, ask me some time what the term "rule of thumb" means) in dealing with bloodstains is that if you want to get rid of them, avoid using hot water. That sets them into the fabric, making their removal very difficult. No doubt this is true of other protein-based colors (the red in blood is a protein). Perhaps something of protein nature was on the rug, having grown on the urinary constituents, and the boiling water removed some (the visible running) and set some (the stains). Perhaps one of the urine pigments is the culprit. It would be interesting to just get some dog urine on a white rag, let it dry, then pour boiling water on it and see what happens. If I had a dog I'd try it myself.

Unless the urine was from a Dalmation dog, uric acid is not likely to have been the source of the color, directly or indirectly.

My comments about the C-14 and dye discussions leading to opposite thoughts about Turkmen rug ages was not meant to be taken terribly literally, and I apologize if it caused any confusion.

Steve Price

Subject  :  Re:Paul Mushak's comments
Author  :  Vincent Keers mailto:%20vkeers@worldonline.nl
Date  :  11-16-2000 on 07:09 a.m.
Dear all,

What about green? How do the metal atoms perform? Does an atom think: "Left side for yellow and the right side for blue? Does the yellow attach to the blue? Or the other way around?
If the dye is behaving like I'm told, all the metal atoms are crowded with dye, when boiling. The extra dye, will not attach.

Red run? Maybe because the dye-master wanted a different shade, he applied two different colors. First indigo and then madder. I think I've learned once upon a time, indigo doesn't need a mordant. (Indigo in water is colorless, and only in contact with air, shows some color.) So if the indigo has taken it's place on the yarn, where does it leave the madder? Does the madder attach to the indigo or to the yarn at open spaces, and will it stick?

All this doesn't clarify real "Stray reds", in the center of a white plain.

Best regards,
Vincent Keers

Subject  :  Re:Paul Mushak's comments
Author  :  Marvin Amstey mailto:%20mamstey1@rochester.rr.com
Date  :  11-16-2000 on 09:17 a.m.
Good morning, all.
I accept Wendel's and Steve's speculations about what else might have affected that rug, including the fact that someone may have "played' with the rug before I or the amatuer saw it. For the most part, I believe that good dyes, well-used, do not run.
Best regards,

Subject  :  Re:Paul Mushak's comments
Author  :  Leslie Orgel mailto:%20orgel@aim.salk.edu
Date  :  11-16-2000 on 12:09 p.m.
I would like to know whether Paul Mushak thinks that aluminum mordants might spread (run). If you put a mordanted red area in contact with an unmordanted white, wetted the combination and left them in contact for a substantial time, would any aluminum spread to the white area? If this happened, while it could not explain where foreign dyes comes from, it might explain why ones that require a mordant stick.

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