How do you Stabilise powdery antique leather

[Ginni]

I’ve got a old leather large suitcase that most of the surface of the leather is powdery and want to stabilise it before using it for decorative storage,

It’s wrapped in plastic at the moment to stop the dust from going everywhere,

Has anyone any experience of doing this please?

 

[Aventurine]

I'm also interested in this problem. I have an old volume of Byron bound in gilded leather that does not appear to be rotten or moldy in any way but it is disintegrating.  I have been tempted to coat it in map waterproofing (water based polyurethane) or acrylic transparency medium just to keep it consolidated.  I would like to get my hands on museum quality curatorial stuff instead -- looking into Pliantex, an acrylic product which is intended as an adhesive but can be used for this problem.

https://fineartsconserv.wordpress.com/tag/pliantex/

 

Edited July 29 by Aventurine
adding link

[Aventurine]

Not immediately practical for your problem or mine, but of nerdy interest.

Deterioration related to method of tanning:
https://jcms-journal.com/articles/10.5334/jcms.3972

Pliantex used to stabilize Viking era shoes from a bog in England
https://zero.sci-hub.st/3943/77c9d1e59c1769babb62b2a8f7fc2c62/peacock1983.pdf

 

 

[Littlef]

My guess is that the powdery substance might be mold spores.  I occasionally buy historic military rifle slings / ammo belts, etc.  I see powdery mold spores on them from time to time.  If its mold, it can be difficult to remove.  The mold actually can have a root system that grows into the leather.  you clean it off, and it grows back in a few weeks.  I would first just try to clean it off with a 50-50 mixture of water and vinegar.  I'd also test the leather first some place inconspicuous to make sure it wont affect the finish.  You could also try the same thing with bleach, which is stronger..... but also might have an affect on the leather finish.   Hardware stores have fungicides.  If you try those and the mold keeps coming back, I'd try a specific fungicide.  As always.  Test it in an inconspicuous place before treating the whole case to make sure its not going to affect the leather color/shade/finish quality.