The UK Hallmarking system has offered valuable protection for over 700 years. Compulsory Hallmarking protects all parties; the public who receive a guarantee of quality, the manufacturer who is given quality control and protection from dishonest competitors at a very low cost, and the retailer who avoids the near impossible task of checking standards on all his goods.
Therefore all items being sold as gold, silver or platinum in the UK must be hallmarked to confirm that they meet the legal standard. This cannot be done by the manufacturer or importer; goods must be submitted to one of the four UK Assay Offices, or an Assay Office belonging to the International Convention.
The law applies to everything SOLD in the UK , regardless of where it may have been manufactured. The only items which are exempt are those which are under the legal weight threshold - 7.78 grams for silver.
One of the requirements of the Hallmarking Act 1973 is that all dealers supplying precious metal jewellery shall display a notice explaining the approved hallmarks. This must be the notice produced by the British Hallmarking Council. Dealers Notices are available from The Birmingham Assay Office at a cost of £10.00 each including VAT + prevailing postage costs. http://www.theassayoffice.co.uk/dealers_notices.html.
To summarise:
businesses can sell silver and gold jewellery without a hallmark but they cannot advertise the piece as being gold or silver (only white or yellow metal).