Originally Posted by
QuiltE
@mkc ... I am one of the people who are sensitive to the cheaper metals, and thus, sometimes look for titanium, as I know it is a safe one for me. One example being metal frames for eyeglasses. Now you have me wondering? How do I really know I am getting what I want? Or is the coating what I have been getting?
In the case of prescription glasses, you should be getting fully titanium frames. They're made in part specifically because they're hypoallergenic and safe for those who have metal allergies.
It's the often-inexpensive things that will be gold in color that use TiN (ti-nitride) coatings (although frames not labelled titanium but appear gold in color could be using the coating to give them the gold color.)