Hallmarks and precious metals
As a goldsmith, all precious-metal articles available at Sweet Apple are duly hallmarked, in accordance with the Portuguese Legal Regime for Goldsmithing and Assay Offices (Law no. 98/2015, of 18 August).
Precious metal prices
Check the daily precious metal prices with reference entities.
Hallmark table
The detailed table of legal hallmarks is available on the website of the Portuguese Assay Office (INCM).
Official appraisers
List of official appraisers of precious-metal articles and gemological materials.
How to read the hallmarks
Every precious-metal article bears at least three marks
Responsibility mark
An engraving with a unique and exclusive design, accompanied by a letter or the name of the economic operator, which identifies who is responsible for placing the article on the market.
Assay office mark
Guarantees the fineness of the metal. Each metal has its own symbol: ram (gold), rabbit (silver), hummingbird (platinum) and lynx (palladium), with the fineness shown in Arabic numerals.
Common control mark
An international mark recognised by the member countries of the Convention on the Control and Marking of Articles of Precious Metals, of which Portugal is a party, facilitating the circulation of articles.
Legal fineness
Minimum purity of the precious metal, in parts per thousand (‰)
What the hallmark means
Understand what you are buying, before you buy it.
In Portugal, articles made of precious metals (gold, silver, platinum and palladium) must carry the manufacturer or importer responsibility mark and the official assay (contrastaria) hallmark. These marks guarantee the fineness (purity) of the metal, expressed in thousandths.
The assay office is run by INCM – Imprensa Nacional-Casa da Moeda, the public entity that tests and marks precious metal articles in Portugal. A hallmark is the independent proof that the piece is what the seller says it is.
In short
- The hallmark certifies the metal fineness, not the design or the stones.
- The number shows the parts of pure metal per thousand (e.g. 750 = 18 kt gold).
- Gold-plated or gilded items are not solid gold, even if they look alike.
- Always ask for the invoice: it is your guarantee of origin.
How to check a piece in four steps
Simple checks you can do at home or in store.
Find the marks
Use a magnifier and look at the clasp, the inside of the ring or a small tag. Hallmarks are tiny.
Read the fineness
A number such as 750, 925 or 950 tells you the metal and its purity (see the table above).
Compare with the official chart
Check the hallmark shape in the official table below, to confirm the metal and the mark type.
Ask when in doubt
We help you in store. For an independent opinion, use an authorised appraiser.
Official hallmark table
Legal marks of the Portuguese Assay Office
Source: Contrastaria (INCM), hallmark table in force since 1 January 2021 (Law no. 98/2015, Ordinance no. 374-A/2017 and Notice no. 21026/2020).Open full sizeFrequently asked questions
Clear answers to what customers ask us most.
What is the difference between karats and thousandths?
Karats divide gold in 24 parts: 18 kt is 18/24, i.e. 750 thousandths. In Portugal the legal fineness is shown in thousandths: 375, 585, 750 and 916 are the most common for gold.
Is gold-plated the same as solid gold?
No. Gold-plated or gilded pieces have a thin layer of gold over another metal. It wears with time and use; solid gold carries the fineness hallmark.
Why do prices vary between similar pieces?
The price depends on the weight, the fineness, the labour and design, the stones and the brand. The metal price changes daily with the market.
How do I look after my jewellery?
Avoid perfume, creams and chlorine, store each piece separately and clean it with a soft cloth. We can help with cleaning and repairs in store.
Can I have a piece appraised?
Yes. The assay and appraisal lists are on the official websites linked at the top of this page. Our team can also advise you in store.
What guarantee do I have?
All articles are sold with invoice and legal guarantee. See the conditions on our warranty page.
Questions about an article?
We are happy to answer any question about hallmarks and precious metals.
The information on this page is of a general nature. For questions about a specific article, contact us or consult the Contrastaria.