It has long been accepted that the presence of cadmium implies a condemnation of the authenticity of an ancient gold object, or at least, of the part of the object where the cadmium is detected. An analysis in Paris of a recently excavated object from Roman times has shown cadmium. Meanwhile, systematic observations were made at L.A.R. N. on objects dating from Hellenistic to Byzantine times with different given origins (objects from a museum and from private collections). By using particle-induced x-ray emission with a 3 MeV proton milliprobe (700 mum beam diameter) in a non-vacuum geometry, relative amounts of copper, cadmium, and gold at the surface of more than 30 gold objects expected to be ancient have been determined. Traces or significant concentrations of cadmium have been detected at several points on or in the neighborhood of solders on many objects which seem to be from Roman to early Byzantine times. Cadmium concentrations range 2 to 100 parts per thousand. This range of variation and the relative concentrations of gold, silver, copper, and cadmium at the surface of the objects studied are often different from the figures obtained during analyses of modern soldering alloys. Experiments with the L.A.R.N. proton microprobe (5mum x 10 mum area) allow a still better topographical resolution and more significant comparison of the relative amounts of the elements of interest in modern soldering alloys and supposedly old solders. The usefulness of the microprobe is demonstrated. -- AATA