Although it is not a rule of thumb, it very frequent occurrence in situations when floor tiles test positive for presence of asbestos, associated mastic is also asbestos containing.
Visual inspection of a suspicious material is a mere guess. I have had many instances in which floor tiles where negative for presence of asbestos ( even though their age and characteristics suggested otherwise ) while mastic tested positive, and vice versa floor tiles positive mastic negative or even both were negative.
So before you’re going to spend hundreds or few thousand dollars to remove the material that somebody TOLD you is asbestos do yourself a favor and request the material to be professionally tested by NVLAP and AIHA certified laboratory, there is a chance that these materials are just old but not asbestos containing.
While this was not used in all but ONLY in the some of products, professional asbestos inspection along with asbestos testing performed by certified laboratory is required to confirm presence of asbestos.
If you already had your property inspected by an IDPH licensed asbestos inspector and now you want to compare or shop around for asbestos removal prices call 1st All Around at 773-986-8725