Have you ever heard of “gold ring test” for identification of lead in lipsticks? It claims that if you swipe off a gold ring on streak of a lipstick, and the color changes to black, then you know the lipstick contains lead! From the scientific point of view, this is absolutely FALSE! The dark streak is not a proof for the presence of lead in lipstick at all. Actually, detection of lead in lipstick or any other cosmetics requires precise analytical instruments applied in chemical laboratories.
Is It Possible to Detect Lead in Lipstick by “Gold Ring Test”?