it's believed that the full amount of tax evasion through the jewellery merchants is around Rs 1000 crores.
"as soon as final assessments are made, the whole fraud could exceed one hundred crore," sources included. https://clerk.tax/chronicle/in-gst/gnews/gst-tax-raid-unraveling-a-web-of-tax-evasion-in-the-restaurant-industry/