I'm no mold expert, but....

Do you have brick or stone walls?  What you describe sounds kinda like
calcium "effervescence" -- the minerals are leaching out of your stone, kinda like
the calcium deposits you'd find in an old (leaky) sink.

When our 1894 fire station (now museum) underwent a million-dollar renovation
-- including a massive over-haul to our foundation -- we discovered lots of
"effervescence" on our basement foundation walls and yet our architects and
structural engineers weren't to concerned.  In the end we did some extensive
tuckpointing and low-and-behold the effervescence was removed.

Don't know if this helps or not -- but thought I'd chime in for what its
worth.

 - David -
David Lewis, Curator
Aurora Regional Fire Museum
www.auroraregionalfiremuseum,org

=========================================================
Important Subscriber Information:

The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] . The body of the message should read "help" (without the quotes).

If you decide to leave Museum-L, please send a one line e-mail message to [log in to unmask] . The body of the message should read "Signoff Museum-L" (without the quotes).