Just in case this last message did not get through. My apologies to you
all if this is doubling up.

Begin forwarded message:

> From: Jennifer Barnett <[log in to unmask]>
> Date: January 16, 2004 11:19:01 AM CET
> To: texcons.dis.list <[log in to unmask]>
> Subject: glass beads
>
> Thanks to all those who have responded to my request for advice on wet
> cleaning and fractured/cracked/crazed blue beads that are stitched to
> a Berlin Work embroidery.
> The use of cycldodecane is an interesting possibility but there seems
> to be (at least?) one disadvantage and that is that the canvas will
> also be impregnated, otherwise the beads could not be fully coated on
> the underside where they are in contact with the canvas.
> I find it more clarifying to think things out by writing, so I might
> as well share the process and enjoy the synergy of your responses as a
> bonus. Please bear with me.
>  Closer examination has revealed that the cotton canvas under the
> beads and the securing threads are white while the rest is "aged"
> light brown. The white fibres are strong, perhaps stronger than the
> rest of the canvas. The pH, measured with a 0-14 pH indicator strip,
> is about 8.5. It would appear that the beads have had provided an
> alkaline reserve for the cotton! The pH may or may not rise with time.
> There is no surface efflorescence on the beads. I would prefer to be
> able to wet clean it to lower the pH even though this would probably
> only be a temporary respite. However, the cycldodecane will no doubt
> prevent this. (No, I do not intend to try to lift and rotate each bead
> to coat it inside and out using a tiny brush).
> At this point, I see two possibilities:
> 1 just wet clean and hope that not too many beads will shatter -> loss
> of (some?) beads, saving of canvas (some beads were wet during the pH
> measurement but did not break - hopeful)
> 2 apply cycldodecane and hope that the pH will not continue to rise in
> time -> loss of canvas -> loss of beads (Postponing the problem? How
> likely is this scenario?)
> Ad 2  future loss of beads due to loss of canvas could be prevented by
> securing them to a support layer with a polyester thread. Should the
> canvas and thread rot away, the beads will remain in their original
> position. But I am sure that the handling involved, especially trying
> to pass a needle and thread through these quite small beads (next to
> the original thread or not) would also cause breakage. This is not a
> good idea.
>
> I'll leave it there for now. Responses are very welcome.
>
> Another article on the subject is "Deterioration of beads on an
> Edwardian evening bodice", Annie Lord, in Ethnographic beadwork:
> aspects of manufacture, use and conservation, Archetype Publications,
> 2001
>
> PS
> Since this sudden immersion in the stability problems of glass beads
> in connection with textiles, it seems as though the development of the
> problems is fairly recent or is it just the awareness that is recent?
> I am curious to know if it is a phenomena which needs time to develop
> and become noticable, as was the case with celluloid which seemed to
> disintegrate simultaneously over the whole world in the 80's and 90's.
> If it is a recent general development and not just isolated cases,
> then it would seem to be a urgent subject for research and funding in
> order to save late 19th century and early 20th century beaded costume
> and ethnographic textiles. The problem provides a variety of good
> subjects for students looking for a final project!
>
Jennifer Barnett
historical textiles research & consultation
Oude Looiersstraat 65-67
1016 VH Amsterdam
Netherlands
tel/fax ** 31 (0)20 427 18 27
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