The Singapore Assay Office (SAO) is an independent body that tests and certifies precious metal articles such as gold, silver, platinum and palladium. SAO provides assaying, hallmarking and X-Ray Fluorescence Material Analysis services.

In 1978, SAO achieved recognition as an Acceptable Assayer by the London Gold Market (now known as London Bullion Market Association). This award is only given when the highest levels of assaying expertise is attained. SAO was the first recipient of that award.

Through SAO, hallmarking has been accepted as a voluntary scheme in Singapore. However, many in the jewellery trade realized the importance of the hallmark, especially if they want to export their jewellery overseas. The hallmark assures consumers that the precious metal article conforms to legal standards.

X-Ray Fluorescence Material Analysis

X-Ray Fluorescence Material Analysis is the latest method used by SAO to do testing of precious metal articles. This method is non-destructive, so samples will not be damaged or destroyed. It is also a very quick method, taking about 20 - 30 minutes per test for an accurate result, as compared to the traditional methods taking up to 5 hours to complete. All alloying metals present in the sample can be analyzed, which is to say that not only the gold content can be analyzed, but also other metals present in the sample.

The coating thickness of the sample can be measured with this machine. With this method, jewellery pieces with exquisite designs can be tested, which cannot be done when traditional methods were used due to the high costs of repairing or redoing the item.

X-Ray Fluorescence is used by many assay offices worldwide and is quickly becoming one of the more commonly used methods for testing.