Did you know there is a portion of the population that has a reaction to nickel, the main metal in monel, the most common metal material for eyeglass frames. This can cause a rash on the skin, discoloration, corrosion and pitting of the frame. Beside being uncomfortable, this allergic reaction can decrease the life of your frame. If you have or have had any of these symptoms, you can choose alternative frame materials like titanium or stainless steel. Ask your optician what frames are nickel free and hypoallergenic.