Possible mold on Claybord?


Well-known member
Hello all and Happy New Year...

I recently aquired a large stock of older Ampersand panels. They have been stored in a small, unused and dark room for maybe 10 years, and some of the panels were purchased twenty years ago...There are 56 total, they are mostly Claybord, Claybord Black scratchboard and their economy model The Artist's Panel. There are also 14 Speedball Gessoed Art Boards.. About half of them are unwrapped and six of them (some of each brand) have what looks like small mold specks on the work surface. I have been using Ampersand boards for twenty plus years and have never had them mold. The boards do not appear to have ever been wet, although the house apparently did flood twice...Sustained humidity maybe in that room with no real air flow?

Thoughts? Thank you 😊
I would open one that seems to have the worst spotting and do some tests on it. A Q-tip dampened with bleach water should show if the spots are mold. Then you could sand a spot or two, gesso over one or two and see if you get bleed through. Just try whatever you think of. Sacrificing one board should give you some clues.
That sucks. I love Ampersand gessoboards and clayboards. They are my preferred substraight for painting. I wonder if you could sand them down and gesso them once with Kils, but I would take sno's advice to see if it's for sure mold. It sounds very possible that it is, even though they were wrapped. Kils would not be effective for the clayboard obviously, but maybe some light sanding with very fine grain paper on those would do the trick.