Regan, I understand what you mean about wanting to try one of these sites, at least once. However, if they are charging a fee, they should be able to tell you its entire composition (e.g. metal content), and its manufacture (how it was made) -- along with the circa date.
Back to your pendant. I'm going to guess that it has a cold enamel application and stylistically, it does not appear to be very old. However, if you have a close-up, we should be able to 'see' more.