Does anyone know how to clean a frame mat?

[gtamom]

Hello
We bought a painting on holidays last month and just hung it tonight. I noticed a teeny tiny spec on the cream coloured mat, and tried to blow it off. It didn't move so I flicked it. It then left a purple smudge on the mat! It is tiny, but does ruin the pristine mat. I don't know what it was, it appears to be some sort of purple powder, perhaps from his studio.
I googled, but didn't find anything.
TIA for any suggestions.

Dh is telling me to phone the artist and ask! :O

[gtamom]

Maybe I should post this question in housekeeping?

[Pietafineart]

Your best bet is with a putty rubber - different to a conventional rubber as the putty disintegrates rather than the paper/card. You can get one at any good/specialist art shop or even ebay. Failing that get a new matt cut at a framers - they are quite inexpensive.