The government had given jewellers more than a year to shift to hallmarking and register themselves with the Bureau of Indian Standards (BIS), and they would be allowed to sell only hallmarked jewellery and artefacts made of 14, 18 and 22 -carat gold.
Any violation would attract penalty and imprisonment.
"Due to the lockdown, jewellers have lost almost three months for sales and operations. It will take another 3-4 months before sales get back on track. It is highly likely that they will be left with jewellery with no hallmarking.
"We shall earnestly urge the Centre to extend the deadline to do away with jewellery without hallmarking for another six months till July 2021," All India Gem and Jewellery Domestic Council vice chairman and Senco Gold & Diamonds CMD Shaankar Sen said.
According to jewellers, another six months would not be enough to exhaust their existing stocks.
The hallmarking service providers also support the extension of the deadline. About 40 per cent of the gold jewellery in the industry is not hallmarked.
"The retail sales of gold jewellery have been hit severely in the last two-and-a-half months and the season is lost. No one knows what will happen in the next six months. We will also recommend the government to extend the deadline," Indian Association of Hallmarking Centres president Uday Shinde told PTI.
There is a need for "more purity hallmarking standards", he said, adding that body will discuss with the Bureau of Indian Standards.
India Bullion and Jewellers Association had also demanded for extension of the deadline by a year.
Pankaj Parekh, a veteran in the jewellery industry, said there are purity benchmarks for jewellery which are prevalent in many states and not falling under the three proposed standards.
"So, this aspect has to be looked into," he added.