This is in a drop ceiling.
I don't know when the ceiling was installed.
Send a sample to a lab. There's really no way to know without doing that, though you could try taking one down to see if there is any information marked on the edges or backside that might help to narrow it down.
-
1@milesmeow: The ceiling tiles might have a date of manufacture stamped on them. If it is since about 1976, they probably do not have asbestos. – wallyk Aug 27 '16 at 18:46
