https://labdiamondinsights.com/news/bis-huid-hallmarking-now-covers-341-centres-across-india-what-diamond-and-jewellery-buyers-must-check-before-buying-in-2026 Lab Diamond Insights en 2026-09-03T00:00:00.000Z BIS HUID Hallmarking Now Covers 341 Centres Across India: What Diamond and Jewellery Buyers Must Check Before Buying in 2026