Mark Traxler April 30th, 2013 05:18 PM

Dye testing
Greetings. I have a wonderful old textile with wonderful color and technique. A couple of the colors have "issues," minor dye transfer to adjacent fibers. I'd like to have two of the colors tested as to whether they are natural or synthetic. Does anyone know where this testing can be done? Thanks. Mark

Richard Tomlinson May 1st, 2013 08:42 AM

Hi Mark

How old is 'old'? If you think it might predate synthetics, why not post some pics and see what others think about age? If the general consensus is 'really old', then testing may be irrelevant.

Richard Tomlinson

Marvin Amstey May 1st, 2013 08:59 AM

'morning Mark,
I tried about a year ago to locate a service and could not find one. There was a listing on a web page somewhere in the west, but they never responded. I think that there are a lot of us who would like to find a dye testing service. Attention, Pierre: have you considered a retirement job to provide such a service?

Pierre Galafassi May 1st, 2013 10:30 AM


Originally Posted by Marvin Amstey (Post 14093)
Attention, Pierre: have you considered a retirement job to provide such a service?

I did, Marvin, but my sweet wife does not like the smell of solvents and my cats too are against the idea thumbsdown

Mark Traxler May 1st, 2013 12:10 PM

Greetings Ya'll
The item in question is a tentband. They seem to be the most enigmatic of all textiles, judging from the literature. We can't even attribute a specific band to a specific tribe with any accuracy, let alone date the darn things. I think Peter Hoffmeister saw pictures of my band [thank you Frederik!] and Peter thought "circa 1880." However, others have observed Eagle group II characteristics [very fine cotton/wool plied weft], and that it could be much older. The band is very wide, at 18". Yes, that's right, 18 inches. Wow. The yellow dye has some very slight transfer to adjacent fiber, and only on the back of the piece. To me the color is "natural," and I have done considerable natural dying. But, it would sure be cool to find out for sure! Thanks guys!

Mark Traxler 1 May 1st, 2013 12:59 PM

Hi again: Here is a picture of the piece I'm talking about. You'll get some idea of the scope of this textile. Thank you Steve, for the assist!


Marvin Amstey 2 May 2nd, 2013 08:44 AM

Not to doubt the dating or possible origin, I have been under the impression from reading years ago that bands that wide are rather late editions - certainly after 1875. I once had an 18 inch band with one color clearly synthetic, but most of it was fine. If someone can disabuse me of that notion, please do.

Steve Price 3 May 2nd, 2013 08:52 AM

Hi Marvin

I've read the same thing, but I have no idea what the evidence behind it is. I'd love to believe it's true; my one tent band is 10 or 11 inches wide.


Steve Price

Mark Traxler 4 May 2nd, 2013 09:24 AM

Greetings, Yes that's the hypothesis. Richard Isaacson told me that's anecdotal, and suggested that pieces be evaluated on a case-by-case basis. This one is likely not the oldest textile in my humble collection, true, but it might be the coolest! bravo

Marvin Amstey 5 May 2nd, 2013 11:54 AM

How are you going to display it? My one complete band - also of that width and noted above - was kept rolled. No place to put it and finally sold it for that reason (not the funny color). I still retain 3 very old fragments.

Horst Nitz 6 May 2nd, 2013 01:20 PM

Hi Mark,

"I'd like to have two of the colors tested as to whether they are natural or synthetic."

If you have access to some of the first issues of Hali and if you feel confident to handle potentially hazardous chemicals, it can be done by yourself. If need be I can find out the exact reference for you.



Mark Traxler 7 May 2nd, 2013 03:29 PM

Banding together!
Hi Marvin and Horst,
Mr. Price has already sent me a thorough methodology published by Paul Mushak, in Oriental Rug Review, April 1986. It doesn't seem too daunting, and makes sense. I see that some of the chemicals [ammonia] are readily and cheaply available. And as for hazardous chemicals, I just sprayed boxelder bugs in our neighborhood, and whatever kills them can't be very good for me! I think that I will "have a go" at testing the one troublesome dye, the yellow. I have my preconceived notion about it though! Beware the Heisenberg Principle!

As for displaying, that can be a problem. We only display a few textiles at any given time. My wife seems to think "less is more!" Thanks for the ideas!


Richard Tomlinson 8 May 3rd, 2013 04:01 AM

Hi Mark

I wonder if there is anyone at a local university that could test? I work at a large university and have always been tempted to head down to the science and biology faculties and inquire. Plenty of weird stuff going on there! Never know....

Richard Tomlinson

Patrick Weiler 9 May 3rd, 2013 11:30 AM

To Dye For
It is probably a huge and daunting undertaking to build the database necessary for just cataloging the structure and components of all the dyes one may encounter.
Then you need to build a database of how to test for them individually and in combinations. Then a cross-reference, if it could be reliable, on when each was introduced. Add in all the effects of different mordants, changes in dyes due to washing, age, smoke and contaminants and you have a career-long project just to be able to get started testing a single fabric.
On the other hand, once you have this established you could easily charge $25 to test one dye in a fabric. clap
And you still have the problem of having to test multiple samples to be sure that a single knot or two in a whole rug may be synthetic and all the rest are not. Not to mention the technique of using old wool to make "new" copies.
I realize that this is a rather cup-half-empty perspective on the topic, and I am not an expert chemist to really know how complex and time-consuming the process of establishing the basic database would be. Maybe if Steve Price had started building one instead of founding Turkotek, we could be partway there by now!
There is also the old saying, divide and conquer. If we got enough chemists and laboratories together, similar to using multiple computers to solve complex analyses, the job may go quicker.

Patrick Weiler

Horst Nitz 10 May 3rd, 2013 12:03 PM

Hi all,

I just realized I had the refernce on my computer:

Helmut Schweppe in HALI II Vol 1, p. 24-27: How to distinguish whether a carpet has been dyed with natural or synthetic dyes.

I have gone by those instructions myself in the past.



Marvin Amstey 11 May 3rd, 2013 03:27 PM

Patrick, its the 21st century! When I was researching places for testing, the one I found, and which never responded, was charging $250 per color; that was in the early 70's. I did prevail upon Mark Whiting to test two colors in an old (I thought) Turkmen only to find out one of the reds was a mixture of madder and Poinceau 2R, therefore, not very old. I haven't had the opportunity to do any testing since. However, it is not inexpensive.

Pierre Galafassi 12 May 4th, 2013 01:40 AM

Hi all,

The modern analytic method (HPLC with Diode-array detectors) is, of course, way too sophisticated and expensive for any "cottage dyestuff-analyst".

But the old and reasonably precise TLC (thin layer chromatography) technique is neither very costly nor difficult to use. However, the cottage analyst should limit his ambitions, for the reasons perfectly explained by Patrick : Creating an extensive date-base of dyes, natural and synthetic, is a huge task since hundreds of old- and recent synthetic dyes have been used for dyeing of rug wool over the past 150 years. Besides, samples of most of them will not be easy or even impossible to source.

My suggestion would therefore be to focus only on the 15-20 most important sources of natural colorants traditionally used on rugs. These dried plants and insects can be bought easily on the Net and since only a grams of each dye will be necessary to create the data bank for a TLC operation, it will also be quite cheap.
Ready-to-use TLC plates (preferably with polyamide layer), the minimal required glassware and the dozen of standard solvents, (both for the dye extraction from the wool and for the chromatography itself), can be bought from labware sites on the Net. I would advise to operate in a well ventilated place, (a garage with open door for example).

With this rustic tool one would have a pretty good chance to identify most of the natural dyes present on one’s rug. Of course there would still be the remote possibility that the rug would contain a rare natural dye, of which one has no reference sample.

 Forget about identifying synthetic dyes though.

Who knows, this modest operation could be the start of an Apple-sized mega-company:thumbsup:

Below, please find the most importants natural plant- and insect- sources and the main natural dyes which each of them contains.

Main natural red dyes

main natural yellow dyes

Best regards

Richard Tomlinson 13 May 4th, 2013 08:00 AM

Hi Pierre

Excellent post !!!


richard tomlinson

PS Caveat : you might get arrested for running a meth lab 

Chuck Wagner 14 May 4th, 2013 08:37 AM

...and for people with unlimited resources:


Appl Spectrosc. 2011 Sep;65(9):1017-23. doi: 10.1366/10-06203.
Identification of natural dyes on laboratory-dyed wool and ancient wool, silk, and cotton fibers using attenuated total reflection (ATR) Fourier transform infrared (FT-IR) spectroscopy and Fourier transform Raman spectroscopy.
Bruni S, De Luca E, Guglielmi V, Pozzi F.

Dipartimento di Chimica Inorganica, Metallorganica e Analitica "Lamberto Malatesta", Universitą degli Studi di Milano, via G. Venezian 21, Milano, Italy.

Attenuated total reflection (ATR) infrared and Fourier transform (FT) Raman spectra were obtained from wool threads dyed in the laboratory with natural dyes used in antiquity, following a procedure similar to ancient methods for dyeing wool. The ATR spectra were primarily dominated by the signals of the wool, making it difficult to identify the dye on the fibers only by visual inspection of the infrared spectrum. However, the Raman spectra showed more significant characteristics attributable to the dyes as previously studied in the literature on modern synthetic dyes. A library-search method was thus applied to the second derivatives of both the ATR and Raman spectra to verify the possibility of identifying the dye. Two libraries were constructed, one consisting of the ATR spectra of undyed wool (raw, washed, and mordanted) and the transmission spectra of pure dyes and the other consisting of the Raman spectra of undyed wool and of pure dyes. Correlation and first-derivative correlation search algorithms were used. The results presented here suggest that the two types of spectroscopy are complementary in this kind of work, allowing the almost complete identification of historic dyes on wool. In fact, through the combined use of the two searches, most dyes were identified with a good index of similarity and within the first five hits. Only for annatto was identification totally impossible using either technique. Subsequently the same method was applied to wool, silk, and cotton threads taken from ancient Caucasian and Chinese textiles.

© 2011 Society for Applied Spectroscopy
Chuck Wagner

Patrick Weiler 15 May 4th, 2013 10:32 AM

I know what I know but I don't know what I don't know
You have almost convinced me to start a dye testing lab on the back patio. It would solve two problems. One, I find out if my rugs are naturally dyed and two, I can irritate my annoying neighbor.
You indicate it may not be too complicated to determine if your rug contains naturally-dyed substances. How, though, do you distinguish if a piece of wool contains a natural dye - proved by your test - but does not also have a synthetic dye mixed with it that is not in your database? The test would be positive for the natural dye, but it would not tell you that there is also another component and whether or not it is synthetic.
My collection acquisition strategy is to buy only the cheapest possible scraps of crap I can find.

That way, I am assured that finding synthetic dyes does not reduce the value my collection.

Patrick Weiler

PS: I have, knowingly, purchased pieces with likely synthetic dyes. They are acknowledged to be "of an age" when pieces of their type were known to have been woven and most of which contain synthetic dyes. This is like many collections of Transitional-phase Navajo rugs which often contain synthetic dyes. Let me tell you, some of those ain't cheap.

Pierre Galafassi 16 May 4th, 2013 11:14 AM

Right, Patrick,

The minimalist approach I suggested has indeed a little problem.
If a dye can't be identified it is:
- either a synthetic dye (one of hundreds)
- or a natural dye of which you don't own any reference sample yet in your data bank.

However, with the plants and insects listed above, after reading of a few books on TLC of natural dyes (the best by far being Helmut Sweppes' (*)), and with a little experimenting (which will be much fun), you should be able to prove to deadly envious but hapless friends/collectors that the pearls in your collection are full of precious natural dyes, and even perhaps to differentiate between a wool dyed with Rubia tinctoria by cold "fermentation" dyeing (described by Manfred in Salon 134) as opposed to a mere conventional hot dyeing.

Please tell me before you go with the new company to the stock market, I already missed the opportunity with another (Californian) garage company

(*) But Schweppe's is very difficult to find except in some university libraries, I had a copy in my company office for decades, but since its mysterious disappearance, I am looking for a new one without success.

Filiberto Boncompagni 17 May 4th, 2013 11:34 AM

Hi Pierre,

Have a look at this website:

It says it has the downloadable copies of "The 3 Schweppe Dye Books"



Filiberto Boncompagni 18 May 4th, 2013 11:40 AM

Idem for this one:

Pierre Galafassi 19 May 4th, 2013 11:43 AM

Just to get you started,
These references available on the net will be helpful, I hope.

Helmut Schweppe
JAIC 1979, Volume 19, Number 1, Article 3 (pp. 14 to 23)

Practical information for the identification of dyes on historic textile materials
Helmut Schweppe
Smithsonian institution


Pierre Galafassi 20 May 4th, 2013 11:51 AM

Speedy Filiberto was the quickest. :thumbsup:

Yes, these 3 texts are summarizing Schweppe's maximus opus.
His book however is putting the Bible to shame (as far as weight) and is beautifully illustrated.