Portuguese gold and filigree

Many people bring a piece of Portuguese jewellery home from a trip to the north of Portugal. The small marks on it were struck under Portuguese rules. The UK reads those marks under its own rules.

Filigree

Filigree is a goldsmith's technique. The goldsmith joins fine chains of gold into an open, airy piece. AICEP Portugal Global reports that Portuguese filigree became part of the country's Intangible Cultural Heritage in 2023. It describes the traditional designs as drawn from nature, religion and love. Fish, shells and waves stand for nature, crosses for religion, and hearts, such as the Heart of Viana, for love.

The specification for the craft's certification names Gondomar and Póvoa de Lanhoso as its two centres. Their town councils promoted the certification. The specification names Viana do Castelo as the main example of the popular, traditional market that filigree served.

The "Filigrana de Portugal" mark

In March 2024, Portugal Global reported an agreement between the Portuguese public body INCM and the two municipalities. Under it, Portuguese filigree is certified with the Contrastaria brand. The specification asks the goldsmith to strike a certification punch on the piece. The piece must also carry its legal assay mark before it can be certified.

It also lets the goldsmith make a piece's frame by hand or by machine, including injection, laser cutting and wax moulds. So the certification mark speaks to the filigree technique, and the assay mark speaks to the metal.

The number on Portuguese gold

Gold marks give the fineness in parts per thousand. The certification specification says gold in Portugal is 800 parts gold in every thousand. That is known as 19.2 carat gold. Some pieces are 750, known as 18 carat.

The UK's gold standards are set in Schedule 2 of the Hallmarking Act 1973. They are 375, 585, 750, 916.6, 990 and 999. The mark struck for 916.6 shows the number 916. In the same table, 800 is a standard for silver. The Assay Offices of Great Britain say nobody can detect a piece's gold content by sight or by touch.

Marks in Great Britain and Northern Ireland

The UK and Portugal both belong to the International Hallmarking Convention. Its common mark shows a pair of scales. The Assay Offices say Convention hallmarks from other member countries are legally recognised in the UK. The Convention's gold finenesses are 375, 585, 750, 916, 990 and 999. Portugal's assay office uses the scales-only form by default, because its national hallmark already shows the metal and fineness.

The British Hallmarking Council says Great Britain stopped recognising equivalent EU hallmarks from 1 January 2021. It says Northern Ireland continues to recognise them, and that new stock entering the Great Britain market needs a UK hallmark or the Convention mark.

The Hallmarking Act's offence applies to people acting in the course of a trade or business. It covers describing an unhallmarked article as gold, silver, platinum or palladium, and supplying or offering to supply one. Gold articles under 1 gram and silver under 7.78 grams are exempt. The Assay Offices add that a pre-1950 item may be sold as precious metal without a hallmark, if the seller can prove it is of minimum fineness and was made before 1950.

Bringing a piece home

The UK government sets a personal allowance for goods that travellers bring into Great Britain from outside the UK. On 19 October 2026, GOV.UK gave the allowance for other goods as £390, or £270 for arrivals by private plane or boat. Over the allowance, tax and duty are due on the total value of the goods.

The British Hallmarking Council's advice for shoppers in the UK is to ask whether a piece is hallmarked. Hallmarks can be tiny, and it suggests asking for a magnifying glass.

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