Made Armstrong Cork Company, LAncaster PA. Instructions for installation date from 1974.
It's a possibility, but there is no way to tell by physical inspection. To resolve this, follow christophern's suggestion and have a local certified lab test it.
Oh god...Armstrong still makes tiles, so call them and tell them the age and type, they will tell you.
Kind of doesn't matter now. The idea is to test potential sources (by a certified lab) BEFORE you rip it down and breathe in all the carcinogenic dust and contaminate your home.
You can't tell by looking.
Sometimes you just don't think of it in advance, so don't feel bad. I for one think there is a good chance it isn't, but having done what you've evidently done, I too would suggest that you want to know. Among other things, around here you have to dispose of asbestos differently.
Look in the yellow pages under labs. I haven't had anything tested yet, but the one I called said that they need at least 3 Tbsp of material and it costs around $45.
Well, all is well that ends well. I emailed armstrong corporate Friday, and got this response today:
Armstrong has never manufactured an asbestos-containing ceiling tile or panel.
Armstrong World Industries
2500 Columbia Avenue
PH - 877 276 7876, option 1,2,3
Also, I found this link:
What do your mineral fibre tiles consist of?
Our mineral fibre tiles are made from a combination of the following naturally occuring, processed and recycled materials in varying proportions depending upon the tile type: mineral wool, clay, perlite, cellulose and starch mixed together in a water based process before being cured by heat. They are then finished with a water based paint, or laminated scrim and paint, decorative facing. All these materials are environmentally safe and our factories comply with ISO 14001.
Note: Asbestos, in any form, is not and never has been used in the manufacture of Armstrong ceiling tiles.
Hopefully they aren't lying, but given all of the litigation (and the fact that they made lots of other ACMs), I really don't see how lying would help them at this point. Hopefully this will help someone else.
Oh, and FWIW, I think the tile contained fiberglass since I itched likeI haven't itched since I was a kid and encountered that pink insulation. Still a good idea to protect your whole body and the house.