The legal metrology department has sent a proposal to the state government to purchase an XRF machine which is used to measure the purity of gold. The move is aimed at ensuring that jewellers do not cheat customers by selling them lower- karat gold jewellery.
“Jewellers are supposed to mention clearly in the purchase bill or receipt the purity of the gold they sold to customers so that the gold can be tested in case of a doubt later,” said RP Thakur, controller of legal metrology. At present, many shops do not mention the purity of gold on the purchase bills leaving legal metrology officials helpless to come to buyers’ rescue.
A karat rate denotes the purity of the gold. An 18-karat gold ornament, for example, means that the jewellery is made of 75 percent of gold and the remaining 25 percent includes other metals like copper, nickel, silver, zinc and palladium. A 24- karat gold is the purest as an ornament of that karat is made completely of gold.
“A karat machine will check the accuracy and correctness using the certified reference materials of the ornament,” Thakur explained.
If any shop delivers an ornament of a lower karat value instead of the one specified to the customer, it can be fined under Section 30 of the Legal Metrology Act, 2009. In the past few months the department has booked several jewellers for not using accurately calibrated weighing machines and for cheating customers. Checking the purity of gold also comes under its purview but the department does not have a machine to do so.
Measurement of gold purity
Gold purity is measured in terms of 10, 14, 16, 18, 20, 22 and 24 karats, with the lowest indicating the presence of a higher percentage of other metals in the ornament. The highest karat means that the gold is pure and unalloyed with no traces of any other metal in the ornament.