International Journal of Science, Engineering and TechnologyAuthors: Ghuge Renuka Sanjay, Professor Abhishek Popat Bangar, Professor S. B. Bhosale, Dr. A. A. Khatri
Abstract: This review explores non-destructive testing (NDT) methods for authenticating and characterizing gold jewellery, bullion, and gilded cultural heritage artifacts without causing physical damage to the samples. Because gold is frequently targeted for counterfeiting using materials like copper or tungsten, traditional destructive assays are increasingly being replaced by rapid, non-invasive analytical techniques. This review synthesizes three key research studies by examining low-cost automated detection for bare and packaged gold items using acoustic impact sound frequency analysis and high-resolution image processing with convolutional neural networks and support vector machines, which achieve high classification accuracy. Additionally, it incorporates the application of portable X-ray fluorescence (p-XRF) spectrometry to analyze historic architectural gilded wall ornaments in-situ. By detecting negligible gold content alongside a characteristic zinc and copper proportion, these elemental analyses successfully rule out genuine gold and identify the use of brass-powder-based imitation paint over a lime-plaster substrate. Together, these works highlight the effectiveness, accuracy, and complementarity of NDT methods—ranging from computer vision and acoustics to elemental spectroscopy—for reliable authentication and conservation decision-making.
