[Nhcoll-l] How to display herbarium specimens without color fading

[Robert Waller]

Hi Rebecca,
Always good to try some informal experiments. Indeed, it is not surprising that filtering UV would not reduce fading rate. It is interesting to compare how chlorophyll "sees" light with how people see light (see, for example, https://www.demegrow.com/blogs/research/70623171-what-plants-see-separating-lumens-from-effective-par-epar)
In a broad Getty Conservation Institute study (attached) removing oxygen during exposure led to a 10 to 20 times reduction in discoloration of herbarium specimens provided by the Canadian Museum of Nature. That seems like a pretty good reduction but, when you think about it, that just changes the lifetime on exhibit from a few months to a few years. Strategies to limit light levels and exposure times would help and I can imagine some other strategies to reduce loss in value (perhaps protecting a part of the specimen from light would reduce the loss of value by keeping that part unaltered). I think that would be interesting to discuss with curators, researchers, and other collection users but I think we do best to consider display of herbarium specimens  a consumptive use of the color of those specimens.
Rob
Robert Waller, PhD, CAPC, FIIC
President and Senior Risk Analyst
Protect Heritage Corp.
622 Simoneau Way
Ottawa  ON  K4A 1P4
email: rw at protectheritage.com<mailto:rw at protectheritage.com>
internet: www.protectheritage.com<http://www.protectheritage.com/>
phone: 613-883-2707 (Canada)
phone: 303-872-9739 (USA)
[cid:image001.gif at 01D8321A.B4062630]http://orcid.org/0000-0002-9500-4113
skype: rrwaller
and, Research Associate, Canadian Museum of Nature
and, Adjunct Assistant Professor, Queen's University
[iic_fellowship_logo_2019]           [cid:image003.png at 01D8321A.B4062630]         [cid:image004.png at 01D8321A.B4062630]
  [ProtectHeritage_logo] <http://www.protectheritage.com/>    [QueensLogo_colour]    [cmn_logo] <http://www.nature.ca/>

        [image007] <http://www.facebook.com/ProtectHeritageCorp?ref=tn_tnmn>           [image009] <https://twitter.com/#!/ProtectHeritage>



From: Nhcoll-l <nhcoll-l-bounces at mailman.yale.edu> On Behalf Of Hawkins, Rebecca Keanni
Sent: March 5, 2022 5:11 PM
To: nhcoll-l at mailman.yale.edu
Subject: [Nhcoll-l] How to display herbarium specimens without color fading

Hello everyone,

Is there a way to display herbarium specimens without color fading? As I understand it, exposing an herbarium specimen to sunlight (and maybe even artificial light?) will cause the specimen's colors to fade to various shades of brown. This question isn't for any specific project or exhibition, just something I've been curious about ever since I helped an herbarium make a small university display and its specimens turned brown after a few months of summer sun.

I did try an informal experiment where I put an herbarium specimen in a glass picture frame with UV blocking window film. However, the specimen's color faded just as fast as a control specimen without the film. This suggests that there was fault with the film itself or my application of it, or even that UV light alone is not what is causing the color of herbarium specimens to fade.

Any ideas? Thanks!

Rebecca Hawkins (she/her)
M.A. Student in Museum Studies
University of Kansas
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.gif
Type: image/gif
Size: 1221 bytes
Desc: image001.gif
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0001.gif>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 28913 bytes
Desc: image002.jpg
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0001.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.png
Type: image/png
Size: 39650 bytes
Desc: image003.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0007.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image004.png
Type: image/png
Size: 10846 bytes
Desc: image004.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0008.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image005.png
Type: image/png
Size: 21440 bytes
Desc: image005.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0009.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image006.png
Type: image/png
Size: 50261 bytes
Desc: image006.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0010.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image007.png
Type: image/png
Size: 22085 bytes
Desc: image007.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0011.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image008.png
Type: image/png
Size: 24715 bytes
Desc: image008.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0012.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image009.png
Type: image/png
Size: 34674 bytes
Desc: image009.png
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0013.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Large scale assessment of light induced color change in air and anoxic environments.pdf
Type: application/pdf
Size: 562742 bytes
Desc: Large scale assessment of light induced color change in air and anoxic environments.pdf
URL: <http://mailman.yale.edu/pipermail/nhcoll-l/attachments/20220307/0d4d82ac/attachment-0001.pdf>