Jewellery can be chosen for its colour, shape, symbolism or the memories associated with it. Yet two pieces that look almost identical may be made from entirely different materials, with different properties, maintenance requirements and prices. Understanding what a piece of jewellery is made from helps customers choose products that suit their preferences and intended use.
Material information is also an important part of product transparency. A manufacturing country tells us where a product was made, but it does not necessarily reveal the origin of its raw materials or explain how those materials behave during everyday wear. Knowing the difference between sterling silver, gold-filled jewellery, plated metals, natural stones and synthetic materials provides a more complete picture.
This guide covers precious metals, common jewellery alloys, surface treatments, pearls, gemstones, lava stone and other materials used in jewellery. It also explains substances that may cause allergic reactions, the meaning of common jewellery markings and the basic principles of jewellery care. The aim is to make technical information understandable without suggesting that one material is automatically the best choice for everyone.
Key Takeaways
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Alloys are normal. Most gold and silver jewellery is made from alloys. The exact composition affects colour, durability and skin compatibility.
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Plating is not solid metal. Gold-filled, gold-plated and vermeil pieces are constructed differently, so check the specification and the underlying metal.
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No material suits everyone. Nickel, cobalt and palladium can cause contact allergies. Terms such as "hypoallergenic" and "surgical steel" do not identify a single material composition.
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Hallmarks need context. A number alone is not proof of authenticity, and certain lightweight precious-metal articles may legally have no mandatory marks.
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The most delicate component determines the care routine. Pearls, porous stones and textile cords may require gentler treatment than the metal parts of the same piece.
Precious Metals: Silver, Gold, Platinum and Palladium
Precious metals have been used in jewellery for centuries, partly because of their appearance and partly because of their physical properties. However, jewellery sold under names such as gold and silver is often made from alloys rather than pure metals. An alloy combines a precious metal with other elements to achieve particular characteristics, including colour, hardness and workability.
Sterling silver is one of the most familiar examples. It contains at least 92.5% silver, with other metals making up the remainder. Copper is commonly used in sterling silver alloys, although the exact composition may vary. Sterling silver can tarnish through reactions with substances in its environment, but tarnishing does not mean that the underlying silver has been permanently damaged.
An example of contemporary sterling silver jewellery is the Frames Silver Earrings by Lisa Kroeber Jewellery, handmade in Estonia. The design illustrates how sterling silver can be used in modern jewellery without relying on elaborate decoration. Its material description identifies the main metal, although the composition of every component remains relevant for customers with specific sensitivities.
Gold jewellery is available in different purities, commonly described in karats. Eighteen-karat gold contains 75% gold, while fourteen-karat gold contains approximately 58.5%. The remaining metals affect the colour and mechanical properties of the alloy. White gold, for example, is not a separate naturally white form of gold but a gold alloy containing other metals.
Platinum and palladium are also used in jewellery, particularly in higher-priced pieces and certain precious-metal alloys. Their properties differ from those of gold and silver, and the precise alloy remains important when evaluating durability or skin compatibility. No precious-metal category should automatically be described as suitable for every person with sensitive skin. [1, 2]
Palladium can also cause allergic contact dermatitis. Some people with nickel allergy may also show sensitivity to palladium, although the relationship between the two is not straightforward and may involve different mechanisms. A confirmed allergy should be assessed individually rather than assuming that one metal is necessarily a suitable substitute for another. [5]
Understanding Gold-Filled, Gold-Plated and Vermeil Jewellery
Not every gold-coloured piece is made from a gold alloy throughout. Some jewellery has a base metal covered by a layer of gold, and the method used to apply that layer affects the product's construction. These distinctions are particularly important when comparing prices, maintenance requirements and potential wear.
Gold-filled jewellery has a layer of gold alloy mechanically bonded to a base metal. Under US Federal Trade Commission guidance, the unqualified term gold-filled generally requires a gold-alloy layer representing at least one twentieth of the weight of the metal in the article, together with other applicable conditions. This is a US trade description rather than a universal European hallmarking standard, so buyers should check the actual construction and gold content of products marketed under similar terminology. [2]
Gold-plated jewellery has a gold coating applied over another material. Its thickness can vary considerably, so the words gold-plated alone do not tell the customer how long the finish will remain unchanged. Frequent friction, contact with chemicals and the construction of the underlying metal can all affect the appearance of a plated piece.
Vermeil is a term commonly used for gold-plated sterling silver. Under US guidance, it has specific requirements concerning the underlying silver, gold purity and coating thickness. Customers should check the actual specification rather than assume that every product described as vermeil has identical construction.
Rhodium plating is another familiar surface treatment, particularly on silver and white gold jewellery. It produces a bright finish and can influence the appearance and surface behaviour of the piece. Like other coatings, it may wear over time, especially on surfaces exposed to frequent friction.
Jewellery Materials Comparison: Metals and Other Common Materials
The following table summarises the main properties of widely used jewellery materials. It includes both traditional precious metals and more affordable materials that can be entirely appropriate for well-designed jewellery. The everyday-use column describes general suitability, not a guarantee of durability or freedom from allergic reactions.
| Material | Main characteristics | Everyday use | Care and important considerations |
|---|---|---|---|
| Sterling silver (925) | Silver alloy containing at least 92.5% silver | Often suitable | Can tarnish. Use appropriate silver care methods. |
| Fine silver (999) | Very high silver content, generally softer than sterling silver | Depends on design | More easily scratched or deformed. |
| Gold alloys | Gold combined with other metals in different proportions | Often suitable | Hardness, colour and possible allergens depend on the alloy. |
| Gold-filled | Mechanically bonded gold-alloy layer over a base metal | Often suitable | Check the gold specification and underlying metal. |
| Gold-plated metal | Base metal covered by a gold coating | Depends on coating | Plating can wear, particularly with frequent friction. |
| Gold vermeil | Gold-plated sterling silver under commonly used trade definitions | Often suitable | Check coating thickness and care requirements. |
| Rhodium-plated metal | Metal with a rhodium surface coating | Often suitable | Surface finish can wear over time. |
| Platinum | Dense, corrosion-resistant precious metal | Often suitable | Can develop surface scratches and a patina. |
| Palladium | Precious metal used in jewellery and alloys | Often suitable | Check the exact alloy and possible sensitivities. |
| Stainless steel | Corrosion-resistant alloy available in different grades | Often suitable | Some grades contain nickel. |
| Titanium | Lightweight, corrosion-resistant metal | Often suitable | Check the grade and any surface treatment. |
| Brass | Copper-zinc alloy with a warm, gold-like colour | Depends on finish | Can tarnish or cause temporary skin discolouration. |
| Copper | Reddish metal that develops a patina | Depends on design | Oxidation may leave temporary marks on skin. |
| Bronze | Copper-based alloy, commonly containing tin | Depends on finish | Can develop a darker surface patina. |
| Aluminium | Lightweight metal, often coloured or anodised | Often suitable | Surface treatments may scratch or wear. |
| Tungsten carbide | Very hard material used particularly in rings | Depends on design | Scratch-resistant but may fracture under strong impact. |
| Ceramic | Hard, non-metallic material used in contemporary jewellery | Depends on design | Can chip or fracture under impact. |
| Silicone | Flexible synthetic material used in jewellery and fittings | Often suitable | Check product-specific composition and wear. |
Material quality should not be judged by price alone. Stainless steel, aluminium and brass can all be used in carefully designed jewellery, while an expensive precious-metal piece may still require regular maintenance. The most useful information is the exact material specification together with the construction and intended use.
Contemporary jewellery also demonstrates how different materials can be combined in one piece. The Folia Bold Earrings by Lentsius use stainless steel for their decorative elements and silicone for their backings. This distinction matters because the decorative element and the components touching the skin may have different properties.
For customers with known metal sensitivities, even a detailed material name may not be enough. The composition of the alloy, the metal used beneath a coating and the components that touch the skin can all be relevant. These considerations are explored in the allergy section below.
Pearls, Gemstones and Natural Jewellery Materials
Metals are only one part of the jewellery world. Pearls, mineral gemstones, volcanic stone, glass, wood and other materials can create very different textures and visual effects. Their characteristics also affect how a piece should be worn, stored and cleaned.
Pearls are organic gems produced by molluscs. Most pearl jewellery available today uses cultured pearls, which are grown through human intervention in freshwater or saltwater environments. Natural and cultured pearls are both genuine pearls, but they should not be confused with imitation pearls made from glass or other materials.
Pearls are relatively soft and can be damaged by abrasion, heat and chemicals. Perfume, hairspray and certain cosmetics may affect their surfaces, so pearl jewellery is best put on after applying such products. Gentle cleaning and separate storage help protect the surface from unnecessary wear. [3]
For an example of pearls combined with precious metal, see the Solid Pearl Drop Earrings by MyaMoon. Their product description identifies freshwater pearls and sterling silver, with different surface-finish options. Jewellery combining pearls and metal should be cared for according to the requirements of both materials.
Gemstones vary enormously in hardness, toughness and sensitivity to heat or chemicals. Diamonds, sapphires and rubies are relatively hard, while stones such as opal, turquoise and malachite can require more careful handling. Hardness describes resistance to scratching, but it does not necessarily indicate resistance to breaking or chipping.
Some gemstones are treated to modify their colour or clarity. Treatments may involve heat, oils, dyes, resins or surface coatings, and certain treatments affect the appropriate cleaning method. A gemstone's name alone may therefore be insufficient to determine how it should be maintained. [4]
Natural and Decorative Materials Comparison
| Material | Main characteristics | Care and considerations |
|---|---|---|
| Freshwater cultured pearls | Genuine pearls cultivated in freshwater molluscs | Protect from abrasion, perfume and harsh chemicals. |
| Saltwater cultured pearls | Cultured pearls grown in marine molluscs | Gentle cleaning and careful storage are important. |
| Diamonds | Very hard gemstones | Settings can still be damaged, and stones can chip under impact. |
| Sapphires and rubies | Corundum gemstones with high hardness | Check for treatments and follow suitable care instructions. |
| Quartz, amethyst and rose quartz | Widely used varieties of quartz | Protect from strong impacts and unsuitable chemicals. |
| Opal | Gemstone with variable water content and structure | Avoid excessive heat and sudden temperature changes. |
| Turquoise and malachite | Decorative stones that may be porous or sensitive | Avoid harsh cleaning, prolonged soaking and solvents. |
| Lava stone | Porous volcanic rock, often used as beads | Avoid prolonged soaking and unnecessary exposure to oils. |
| Cubic zirconia (CZ) | Laboratory-made diamond simulant | Can be scratched or damaged by abrasion and impact. |
| Moissanite | Usually laboratory-grown gemstone material | Hard and suitable for many jewellery designs. |
| Glass and crystal glass | Decorative materials available in many colours | Can chip, scratch or break. |
| Resin and acrylic | Lightweight synthetic decorative materials | Protect from excessive heat, solvents and abrasion. |
| Wood | Lightweight natural material | Avoid prolonged moisture exposure. |
| Leather and textile cords | Flexible components used in necklaces and bracelets | Care depends on the exact material and finish. |
Lava stone deserves particular attention because its porous texture is part of its appearance. It is often used in beaded bracelets and necklaces, sometimes combined with metal components or elastic cords. The durability and cleaning requirements of the complete piece therefore depend on more than the stone itself.
Some lava stone jewellery is marketed for use with fragrances or essential oils. However, not every lava stone accessory is designed for this purpose, and oils may irritate the skin or affect other components. Customers should follow the manufacturer's instructions and avoid applying oils to jewellery unless the product is specifically intended for that use.
A similar principle applies to jewellery containing several gemstones or decorative materials. A necklace may include durable metal fittings alongside delicate pearls, dyed stones or a textile cord. The most sensitive component should guide the cleaning method.
Jewellery Allergies: Which Materials Need Extra Attention?
Jewellery allergies are an important consideration for customers who experience itching, redness or irritation after wearing certain pieces. Allergic contact dermatitis occurs when the immune system reacts to a substance following sensitisation. It differs from simple skin irritation caused by friction, moisture or other non-allergic factors.
Nickel is one of the best-known causes of jewellery-related contact allergy. Cobalt is another recognised metal allergen, and both can occur in metal alloys. People who react to gold- or silver-coloured jewellery may sometimes be reacting to an alloying metal or the material beneath a surface coating rather than to the visible precious metal itself. [5]
Not all substances of concern are allergens. Lead and cadmium are restricted in jewellery primarily because of their toxicological properties. It is important to distinguish these hazards from contact allergy rather than place them all under the same medical explanation.
Materials and Substances Requiring Particular Attention
| Substance or material | Main concern | Practical advice |
|---|---|---|
| Nickel | Common cause of allergic contact dermatitis | Check compliance with nickel-release requirements, especially for earrings. |
| Cobalt | Recognised cause of metal contact allergy | Consider the exact alloy if cobalt allergy has been diagnosed. |
| Chromium(VI) | Can cause sensitisation and has other health hazards | Relevant particularly to leather components, rather than metallic chromium in alloys. |
| Unknown base-metal alloys | Unclear composition and possible allergens | Request detailed material information. |
| Brass | Copper-zinc alloy whose composition can vary | Check the alloy and whether the finished product meets EU restrictions. |
| Nickel-containing metal beneath plating | Exposure may change as a coating wears | Check the underlying material, not only the visible finish. |
| Lead | Toxicological concern | Jewellery placed on the EU market must comply with applicable restrictions. |
| Cadmium | Toxicological concern | Jewellery and relevant components are subject to strict EU limits. |
| Certain adhesives, dyes and resins | Some formulations may cause contact reactions | Consider the actual ingredients when a sensitivity is known. |
European Union chemical restrictions apply to jewellery placed on the market, regardless of where it was manufactured. Tukes, the Finnish Safety and Chemicals Agency, identifies restrictions involving nickel, cadmium, lead and chromium(VI) in relevant product materials. For nickel, the requirements focus on the amount released from relevant jewellery surfaces rather than simply prohibiting every alloy that contains nickel. In jewellery containing leather components, chromium(VI) restrictions may also be relevant. [6]
For example, jewellery intended for insertion into pierced parts of the body is subject to a nickel-release limit of less than 0.2 micrograms per square centimetre per week. Jewellery intended for direct and prolonged skin contact is subject to a different limit of 0.5 micrograms per square centimetre per week. These are product safety requirements, not guarantees that every individual will avoid a reaction. [6]
Terms such as hypoallergenic, nickel-free and surgical steel should therefore be interpreted carefully. Hypoallergenic does not mean that a product is incapable of causing an allergic reaction, while surgical steel does not identify one universal alloy composition. Customers with diagnosed allergies should consider the actual materials and relevant product information rather than relying on a marketing term.
The marking 316L is a good example of why details matter. It identifies a stainless steel grade that generally contains nickel as part of its alloy composition. The amount of nickel released during wear depends on the material and its surface condition, so the grade designation alone does not guarantee suitability for someone with a diagnosed nickel allergy.
The Leaves Small Earrings by Lisa Kroeber Jewellery combine brass and sterling silver. This illustrates why material information should describe more than the main decorative element. Customers with known metal sensitivities should consider the materials of the complete piece, including the parts that touch the skin.
This guide provides general information about jewellery materials and does not replace the assessment of a healthcare professional. If you have a diagnosed allergy or recurring skin symptoms, a doctor or dermatologist can help identify relevant allergens. The findings can then be used when evaluating the materials of a particular piece of jewellery.
What Do Jewellery Hallmarks and Material Markings Mean?
Jewellery may carry small numbers, letters or symbols on the inside of a ring, near a clasp or on another metal component. Some are official precious-metal markings, while others are commercial abbreviations or descriptions of a material or coating. Understanding the distinction can help customers interpret product information more accurately.
A fineness mark indicates the minimum proportion of a precious metal in an alloy, usually expressed in parts per thousand. For example, 925 indicates a silver content of at least 92.5%, while 750 indicates a gold content of at least 75% when used as the relevant gold fineness mark. The complete marking, including the metal identification and any required responsibility or assay marks, is important when assessing an article. [1]
Common Jewellery Markings
| Marking | Meaning | Important distinction |
|---|---|---|
| 925 / Ag925 | Sterling silver, at least 92.5% silver | Fineness indication, not an allergy guarantee. |
| 800 / 830 | Silver fineness marks of 80% and 83% | Lower silver content than sterling silver, also found in older jewellery. |
| 999 / Ag999 | At least 99.9% silver | High silver content, generally softer. |
| 375 / 9K | Gold content of 37.5% | Commonly described as 9-karat gold. |
| 585 / 14K | Gold content of approximately 58.5% | Commonly described as 14-karat gold. |
| 750 / 18K | Gold content of 75% | Commonly described as 18-karat gold. |
| 916 / 22K | Gold content of approximately 91.6% | Commonly described as 22-karat gold. |
| 950 / Pt950 | Platinum content of at least 95% | Metal identity matters alongside the number. |
| 950 / Pd950 | Palladium content of at least 95% | Same number, different precious metal. |
| 316L | Stainless steel grade designation | Not an official precious-metal hallmark. |
| GF | Gold-filled | Commercial construction description. |
| GP | Gold-plated | Does not alone indicate plating thickness. |
| RGP | Rolled gold plate | Not solid gold. |
| CZ | Cubic zirconia | Identifies a gemstone simulant. |
Older silver jewellery may carry fineness marks other than 925. The full marking, the item's age and its country of origin are therefore worth considering when assessing it. A number should not be interpreted without understanding which metal it identifies.
For plated precious-metal jewellery, a fineness mark identifies the underlying precious metal rather than the surface coating. A gold-plated sterling silver article may therefore carry a silver fineness mark such as 925. This distinction is important when interpreting markings on jewellery that has a different surface colour from its underlying metal. [1]
In Finland, qualifying precious-metal articles generally require a fineness mark together with a registered responsibility mark or an accepted assay office mark. However, there are important exemptions. Silver articles weighing less than 10 grams and gold, platinum or palladium articles weighing less than one gram do not have to carry the otherwise mandatory marks. [1]
The absence of a hallmark does not therefore automatically mean that a small piece of jewellery is counterfeit. Conversely, a stamped number should not be treated as conclusive proof of authenticity without considering the full marking and the seller's information. Tukes also distinguishes between mandatory marks, voluntary marks and other permissible markings. [1]
Some jewellery may carry an assay office mark or a Common Control Mark under the international Hallmarking Convention. These marks serve different purposes from simple material abbreviations such as GF or GP. Customers interested in identifying older or more valuable jewellery may benefit from professional assessment rather than relying on a single visible stamp. [7]
How to Choose Jewellery for Everyday Wear
The best material depends on the type of jewellery, how frequently it will be worn and the preferences of the person wearing it. Earrings used occasionally may have different practical requirements from rings worn throughout the day. A bracelet made from beads and elastic cord also requires different care from a solid metal bangle.
For everyday jewellery, it is useful to consider the materials that come into direct contact with the skin. Earring posts, backs, clasps and the inside surfaces of rings may be more relevant to comfort than decorative components that rarely touch the wearer. When a piece has a coating, the composition of the underlying metal may also matter.
Maintenance is another consideration. Sterling silver may need occasional cleaning, gold-plated jewellery may require more careful handling to preserve its finish, and pearls or porous stones should be protected from unsuitable chemicals. Choosing a piece that matches the wearer's habits can help maintain its appearance over time.
Caring for Jewellery: The Basics
Proper care begins with recognising that different materials respond differently to moisture, chemicals, abrasion and heat. Perfume, cosmetics, cleaning agents and swimming-pool chemicals can damage certain metals, coatings and gemstones. Even jewellery that is suitable for regular wear may benefit from being removed during activities that expose it to unnecessary impact or chemical contact. [4]
Pearls and delicate gemstones require particular attention. The Gemological Institute of America recommends avoiding ultrasonic or steam cleaning for pearls and warns that some treated or porous gemstones may also be damaged by unsuitable cleaning methods. Gentle cleaning and following the manufacturer's instructions are safer than assuming that one cleaning solution is appropriate for every material. [3, 4]
Storage matters as well. Hard gemstones can scratch softer materials when pieces are kept together without protection, while chains and delicate fittings may become tangled or damaged. Separate compartments, soft pouches and periodic inspection of clasps and settings can help keep jewellery in good condition.
Why Material Transparency Matters
Material descriptions are not simply technical details. They help customers understand the construction, care requirements and potential limitations of a product. They also make it easier to distinguish between products that may look similar but are manufactured from different materials.
The same principle applies to manufacturing origin. A piece of jewellery may be made in Europe using metals, gemstones or components sourced internationally. Knowing where the finished product was manufactured is valuable, but it should not be confused with knowing the origin of every raw material. To understand why manufacturing origin alone does not establish a product's environmental credentials, read Made in Europe Is Not a Sustainability Label: What Jewellery Buyers Should Know.
At Evoiro, we focus on products manufactured in Europe and believe that customers should have access to clear information about what they are buying. We want the makers, materials and manufacturing locations behind our selection to be understandable rather than hidden behind broad marketing claims. A thoughtful jewellery purchase begins with knowing what a product is, how it should be cared for and whether it suits the person who will wear it.
The distinction between a product's design origin and its actual manufacturing location is explored further in Why “Designed in Europe” Isn't Always Enough. Understanding this difference helps customers evaluate origin claims more accurately. It also explains why Evoiro places particular emphasis on identifying where its products are manufactured.
Explore Women's Jewellery at Evoiro to discover jewellery made in Europe by independent brands and manufacturers. Individual product descriptions provide information about materials, design and manufacturing origin. Together with this guide, those details can help customers compare products according to their own preferences and needs.
Frequently Asked Questions
Is gold-plated jewellery safe for sensitive skin?
It depends on the metal beneath the coating and on how the piece is constructed. Plating can wear with friction and contact with chemicals, which may eventually expose the underlying material. If you have a diagnosed metal allergy, check the base metal and seek professional advice when necessary.
Can sterling silver cause an allergic reaction?
Sterling silver is well tolerated by many people, but it is an alloy rather than pure silver. The metals mixed with silver can vary between products, and some people may react to certain alloying metals. The actual composition and the parts touching the skin are therefore important.
Does "hypoallergenic" mean the product is nickel-free?
No, hypoallergenic does not necessarily mean nickel-free. The term does not guarantee that a product cannot cause an allergic reaction. Detailed material information and relevant safety compliance are more informative than the marketing term alone.
What is the difference between gold-filled and gold-plated jewellery?
Gold-filled jewellery has a mechanically bonded gold-alloy layer over a base metal, while gold-plated jewellery has a coating whose thickness can vary widely. Neither construction means that the entire piece is solid gold. The gold content, coating specification and underlying metal are useful details when comparing products.
Does jewellery without a hallmark have to be fake?
Not necessarily, because certain lightweight precious-metal articles are exempt from mandatory marks in Finland. For example, silver articles weighing less than 10 grams and gold, platinum or palladium articles weighing less than one gram are covered by these exemptions. A stamp alone is not conclusive proof of authenticity either, so the complete product information remains important.
How should I clean pearl jewellery?
Pearl jewellery can generally be wiped gently with a soft, slightly damp cloth and allowed to dry before storage. Ultrasonic and steam cleaning should be avoided, and pearls are best put on after applying perfume, hairspray and cosmetics. Store them separately from harder gemstones to reduce the risk of scratches. [3, 4]
Can I wear a lava stone bracelet in the shower?
It is generally better to remove lava stone jewellery before showering. Lava stone is porous, and repeated exposure to water, soaps and other substances may affect the appearance of the beads or other components. Elastic cords and metal fittings may also have their own care requirements.
Which materials are best for everyday earrings?
The parts that touch the skin matter most, including posts, backs and clasps. Titanium, platinum and certain gold alloys may be appropriate options for some wearers, but the exact composition and construction remain important. Customers with known sensitivities should check the product specifications and follow individual medical advice.
Sources
[1] Finnish Safety and Chemicals Agency (Tukes). Mandatory Marks. Finnish precious-metal fineness marks, responsibility marks and exemptions for lightweight articles.
https://tukes.fi/en/products-and-services/articles-of-precious-metals-jewellery-and-watches/marks-on-articles-of-precious-metals/mandatory-marks
[2] Federal Trade Commission (FTC). Buying Platinum, Gold, and Silver Jewelry. Precious-metal purity, gold-filled, gold-plated and vermeil terminology. The guidance concerns the US market.
https://consumer.ftc.gov/articles/buying-platinum-gold-and-silver-jewelry
[3] Gemological Institute of America (GIA). Pearl Care and Cleaning Guide. Pearl properties, cleaning and storage recommendations.
https://www.gia.edu/pearl-care-cleaning
[4] Gemological Institute of America (GIA). Tips on Caring for Jewelry. Gemstone treatments, cleaning methods, chemical exposure and storage.
https://www.gia.edu/gia-news-research-tips-caring-jewelry
[5] DermNet. Jewellery Allergy. Medical information about contact dermatitis and jewellery-related metal allergens.
https://dermnetnz.org/topics/jewellery-allergy
[6] Finnish Safety and Chemicals Agency (Tukes). Product Safety and Chemicals in Jewellery and Watches. Chemical restrictions applying to jewellery and relevant components.
https://tukes.fi/en/products-and-services/articles-of-precious-metals-jewellery-and-watches/chemicals-in-jewellery-and-watches
[7] Finnish Safety and Chemicals Agency (Tukes). Voluntary Marks. Assay office marks, Common Control Marks and other voluntary markings.
https://tukes.fi/en/products-and-services/articles-of-precious-metals-jewellery-and-watches/marks-on-articles-of-precious-metals/voluntary-marks
