even if a magnet doesnt stick, it could still be plated. either a thick plate or a non-magnetic metal as a base. the rule of thumb is that if it doesnt have a 925 or any sterling mark on it, it is silver plated. UNLESS it is just that old. yours doesnt look that old and my guess is silver plate. even though usually silver plate still has a mark. the only test ive ever used to test silver or silver plate is with nitric acid. be vary careful and in an inconspicuous spot on the bottom, scratch a deep enough scratch where it would hit the base metal. take a dropper and place a SMALL drop on the scratched part. if it turns milky, it is sterling, if it turns red or green, it is plated. be very careful and where gloves. the acid WILL ruin the spot you put it on, so only do this if you dont mind if it gets ruined or if you test it in enough of an inconspicuous place that it doesnt matter. hope this helps, and dont forget if you dont want it to ruin, dont test with nitric acid.
