Instruments designed to ascertain the precious metal content of gold items employ various methods, including X-ray fluorescence (XRF), fire assay, and ultrasound. XRF, a non-destructive technique, analyzes the fluorescent X-rays emitted by the sample when exposed to an X-ray beam. Fire assay, a traditional destructive method, involves melting the sample with lead to separate the gold, followed by chemical analysis. Ultrasonic testing uses sound waves to measure density and detect internal flaws, offering another non-destructive approach to evaluation.
Accurate determination of precious metal content is critical for transactions, appraisals, and quality control in the jewelry industry and gold refining. Historically, touchstones and acid tests provided rough estimates, but these lacked precision and could damage the item. Modern analytical tools offer fast, accurate, and often non-destructive methods, enabling fair pricing and verifying the authenticity of gold items. This technology plays a crucial role in maintaining consumer trust and facilitating efficient trade in the gold market.