A public consultation has been launched into the use of Birmingham Assay Office's famous anchor mark by its base in India.
Changes to the Hallmarking Act, which came into force in early 2013, allow Birmingham and the UK's three other assay offices to open bases overseas.
Last year, Birmingham Assay Office announced it was opening a new branch in India where jewellery could be verified, or 'assayed', with the same anchor mark used in the city since 1773.
But it emerged earlier this year the decision to allow the four assay offices to apply their symbols abroad could be reversed.
Minutes from the British Hallmarking Council's (BHC) meeting in October revealed the council had unknowingly breached an undertaking given by the Government during the process of amending the Hallmarking Act.
The undertaking was that different marks would be required to distinguish between items assayed in the UK and those assayed overseas.
The Government has now opened up a public consultation into this issue which is running over the summer.
It states: "This consultation seeks to understand whether stakeholders would wish articles of precious metals which are hallmarked by UK Assay Offices in their overseas sub-offices should carry a hallmark which is different from the hallmark applied in the UK.
"Responses to this consultation will inform the decisions we will take in respect of hallmarks to be used off-shore and the guidance we will produce for the trade and consumers."
Assay symbols denote the office that verified the jewellery item as opposed to the location where the mark was physically applied or where the jewellery item was actually made.
Jewellery manufacturers fear the same standards of quality will not be applied by Birmingham's sub-office in Mumbai and customers will be unable to tell where an item has been stamped.
But Birmingham Assay Office has argued its base in Mumbai has full approval from the BHC.
Assay offices elsewhere in the European Union and globally have been using overseas sub-offices to assay items which are then available for sale on the UK high street.
Birmingham Assay Office, which is based in Moreton Street in the Jewellery Quarter, says the 2013 changes to the Hallmarking Act have enabled it to be more competitive.
The other UK assay offices are in Sheffield, London and Edinburgh and use the rose, leopard's head and castle symbols respectively.
Sheffield opened a sub-office in Italy in 2014 but this has since closed.
The Government's consultation closes on September 22 - for more details and to lodge your views visit www.gov.uk/hallmarking.
