Abstract-
With the increase of fraudulent conduct in the field of jewellery there has been increase in the demand for inspection to identify the purity of the product. In this case study X-Ray Radiography is used to identify natural pearls and artificially cultured pearls. In order to understand the internal structure a personalized grating interferometer and inspection has been performed to obtain measurements. The computed results are displayed using tomography. The inspection has been performed on three types of pearls a natural pearl, a cultured beaded pearl, and a cultured beadless pearl. The approach can be used for not only a single pearl but inspecting multiple pears like pearl necklace. …show more content…
f) are results of high pass filter on a), b), c) respectively. Figure 4 Natural pearl Figure 5 Saltwater cultured pearl Figure 6 beadless freshwater cultured pearl Figure 7X-Ray imaging of necklace
3. Discussion
The two case studies provide with a valuable information of composition and structure of pearl. The only drawback of conventional absorption technique is layers of pearls are very thin and distribution of layers is un-uniform. Thus image obtained by direct attenuation is very weak and hardly understandable. X-Ray phase contrast method can most efficiently used for such tiny sized objects. Topographical image obtained can reveal type of fissures and quality of it. High pass filer is especially used for obtaining such clear images.
Effect of this filter is highly evident on natural saltwater pearls ( Fig 4a and 4d). Because of this filter enhancement contrast of layers of alternating X ray density is clearly visible.
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