Jewellers Tools Xlarge Gold Silver Platinium Scrap Testing Magnet 24Ct 9Ct Check 4 Fake Goods Gold/Silver Extra largeearth magnets are used on Fine jewellery thatare gold or silverplated where ferrous metals are used as the base metal. If a magnet responds to jewellery, it is not fine silver or anything near pure gold. Samefor brass and bronze antiques, many are just brass plating over a steel or iron core. Keep this magnet in your pocket and test items quickly, The magnet can also be used to determine polished aluminum from stainless steel in most cases. EXTRA LARGE MAGNET 50MM X 30MM X 5MM