The Hallmark Unique Identification Number, which was seen in the news, is associated with which element or product?

A 6-digit alphanumeric code called a Hallmark Unique Identification (HUID) number is exclusive and made up of both numbers and letters. To provide customers with third-party assurance of the purity and fitness of the gold, it is manually stamped on a piece of jewelry. The sale of gold jewelry and other gold artifacts without a HUID number will be illegal in India starting on April 1st, 2023, according to a statement from the Union Ministry of Consumer Affairs, Food, and Public Distribution.