The mystery of dyes ....

[Richard Tomlinson]

Hello all,

I own a pair of Shahsavan (Caucasian) reverse soumak bagfaces. From my experience, based on the feel and range of excellent dyes, these pieces are no later than 1880. But am I wrong?

Pic 1
http://www.turkotek.com/show_and_tell/Rich_Toml_pic1.jpg

Pic 2
http://www.turkotek.com/show_and_tell/Rich_Toml_pic2.jpg

Pic 3
http://www.turkotek.com/show_and_tell/Rich_Toml_pic3.jpg

Pic 4
http://www.turkotek.com/show_and_tell/Rich_Toml_pic4.jpg

Pic 5
http://www.turkotek.com/show_and_tell/Rich_Toml_pic5.jpg

Pic 6
http://www.turkotek.com/show_and_tell/Rich_Toml_pic6.jpg


Pics 1 and 2 and 6 will give you an idea of some of the colours. To me, they seem old and all natural. Great range including various purples, a rose red, teal, and many more. Now ...... let's focus on one colour.

Pic 3 shows you the back with a purple on the left and top right (identical), and on the right, a maroon colour with dark aubergine in the centre. The purple is used extensively in both bags.
http://www.turkotek.com/show_and_tell/Rich_Toml_pic3.jpg

Pic 4 shows you the front of the top right purple (triangle) as seen in pic 3
http://www.turkotek.com/show_and_tell/Rich_Toml_pic4.jpg

Pic 5 - shock and horror - shows you the front of the purple on the left of pic 3. It is completely faded to a brown! Now as I stated, this purple is used extensively in both bags, and yet this is the only place where it has faded to nothing?..
http://www.turkotek.com/show_and_tell/Rich_Toml_pic5.jpg

How is that possible? I am completely at a loss to explain. Can natural dyes fade like this due to some error in the dye process? Why have the other areas with similar purple not faded?

The dye does not look anything like fuchsine, and appears a natural dye (I have seen this in many many Shahsavan pieces)

Any help would be most appreciated.

Regards
Richard Tomlinson

[Filiberto Boncompagni]

Hi Richard,

I can see only two logical explanations for that - assuming I understand correctly the fact that one of the two bags presents both the unfaded and faded purple dye (while in the other one the purple is OK):

1- they used two purple dyes for that bag: one natural, the other was fuchsine.

2- that particular bag used the same natural dye but had the faded spot because it was somehow unevenly exposed to the sun for many years.
:sherlock:
Filiberto

P.S. - it seems that the images arrived to me sideways, which could be a little confusing considered Richard's description. Like 'top right' is not top right anymore, and so on. Sorry about that.

[Richard Tomlinson]

Hi Filiberto

Very deductive thinking!

One thing I will say is that the dye has definitely faded. However, I cannot agree that this is fuchsine. Perhaps another non natural dye, but the colour - in my limited knowledge - looks nothing like fuchsine.

The hard part for me is to try and understand why just one area would fade, and yet other areas not, when the shade of dye seems virtually identical. I will say that some purples in the bag look a little weaker than others (on the back), but then the purple on the front also looks weaker, so there is consistency in that. But to completely fade to what looks more like undyed brown wool .... I cannot fathom.

The other interesting dye is the light blue (almost turquoise). This too has faded in some parts to an almost aqua green colour. Indigo sulphonic dye?

The bags 'feel' old .... 19thC. The wool is very shiny too, much more so than similar reverse soumak pieces I have and have had. It is also devilishly hard to capture the true colour of these pieces.

I wish we had more knowledge of the different dyes used circa 1900 and before....

Regards
Richard

[Filiberto Boncompagni]

I wish we had more knowledge of the different dyes used circa 1900 and before....
Well, at least for the Caucasus we have some information... See 'Dyestuffs in Caucasian textiles' in the Miscellaneous section

http://www.turkotek.com/VB37/showthread.php?t=792 6

[Dinie Gootjes]

Hi Richard,

I know you said it doesn't look like fuchsine, but could fuchsine on that naturally brown wool give that dark purple effect? I also seem to remember that, though 'fuchsine' is technically one dye, there were a number of other similar dyes in use, that are all lumped under the 'fuchsine' label. Maybe one of those, a darker one?

[Pierre Galafassi]

Hi Dinie and all,

You are right Dinie, :clap:
Fuchsine is only one of these very early synthetic dyes with a lousy light fastness.
Other red-, purple- and violet- dyes belonging to a slightly different chemical family (triphenyl methane) have similar poor to terrible resistance to light. Also some early members of the 'azo' dyes family.
(And for that matter, also several old yellow, orange, and green dyes.)

Besides, we can't exclude that the dyer mixed two dyes (some red and a trace of violet for example), to obtain the red shade he had in mind.
'Fuchsine' is used in rugdom literature, a bit abusively, as a code name for all old lousy dyes.

By the way several natural red dyes are known for their very bad lightfastness too, and were used on antique Persian- (so called 'Polonaise'-) , Tibetan- and Chinese rug.
(But it is highly unlikely that one of these natural dyes was used for the case discussed in this mail.

Filiberto's explanation perfectly covers just about all other possibilities.


Best regards
pierre

[Joel Greifinger]

Hi Richard,

Thought you might be interested in this thread about fugitive dyes from 2004, started by...

http://www.turkotek.com/misc_00020/Fuchsine.htm

:deadhorse:
:laughing_2: :laughing_1:
Joel

[Filiberto Boncompagni]

Bravo Joel :clap::clap::clap:

Searching in our archives always gives good results.

Oh my, that was 18 years ago...

Hum, at the time I posted two very interesting links from the 'Journal of the American Institute for Conservation' on

IDENTIFICATION OF DYES ON OLD TEXTILES

and

GENERAL EFFECTS OF AGEING ON TEXTILES

The links are gone now :(

BUT, thanks to my infinite wisdom :laughing_2: AND the WAYBACK MACHINE
https://archive.org/

I was able to recover them (minus the pictures):

https://web.archive.org/web/20120418084645/http://cool.conservation-us.org/coolaic/jaic/articles/jaic19-01-003.html

https://web.archive.org/web/20180126071745/http://cool.conservation-us.org/coolaic/jaic/articles/jaic25-01-004.html

If you are still interested, enjoy them... Again.

Filiberto

[Richard Tomlinson]

Hi everyone and thanks for your input.

I guess the overwhelming thought is that this is a fuchsine or fuchsine related synthetic dye; a 'lousy' dye as it has been referred to. I cannot argue with the fact that it is purple, and that it has faded.

I will end the discussion here, and leave you with these pictures. The first pic (if you care to download and zoom in) will show you the extensive use of purple in this bag (evident in the other bag too).

http://www.turkotek.com/show_and_tell/Rich_Toml_pic7.jpg

The second pic is a collage and compares the back of 4 different medallions with a purple from this bag . One of these purples is the faded dye, the other three are unfaded on the front (or slightly faded as one would expect, but still clearly purple).

http://www.turkotek.com/show_and_tell/Rich_Toml_pic8.jpg

Can you tell the difference in dye lots? If not, perhaps they are all the lousy purple, but for some strange reason, only one has faded.

Regards
Richard

[Filiberto Boncompagni]

The first pic (if you care to download and zoom in) will show you Our software doesn't allow that.
That's why we have to resize the pictures for posting...
What you see is what you get :cool:
Regards,

Filiberto

[Jim Miller]

Filiberto,
The PDF versions of the two papers you cited are available on line to download

The link for "Identification of Dyes in Old Textiles" paper by Helmut Schweppe is
https://www.jstor.org/stable/pdf/3179569.pdf?refreqid =excelsior%3A651ca98 eacdf388c45e20b0dcfb 4b164&ab_segments=&origin=

The link for "General effects of aging on textiles" by Randall Bresee is
https://www.jstor.org/stable/pdf/3179413.pdf?refreqid =excelsior%3A6b21850 86d0f7af394cc7229e32 3637c&ab_segments=&origin=

Cheers
Jim

[Filiberto Boncompagni]

Thanks, Jim.

I already downloaded the first one at the right time from the original website. With pictures.
:cheers:
Filiberto