SINGAPORE - It’s true enough that all that glitters is not gold, but it can be far harder to know just what you are buying when you do splash out on the precious yellow metal. We can judge on appearance and weight, but neither tells you how much gold there is until you use X-ray scanners or get a refinery to extract the precious metal.

The result can be rather disconcerting because most people won’t bother to check the authenticity of their jewellery until they need to sell it.