Chemistry & Metallurgy of Jewellery


REACH stands for Registration, Evaluation, Authorisation and Restriction of Chemicals, and is the EU Regulation (EC) No 1907/2006.

It is the system for controlling chemicals in the EU and became law in the UK on 1st June 2007, replacing a number of directives and regulations with a single system. These legal requirements will remain in UK law immediately following Brexit.

REACH aims to provide a high level of protection of human health and the environment from the use of chemicals, by making the people who place chemicals on the market (manufacturers and importers) responsible for understanding and managing the risks associated with their use.

A substance on its own, in a mixture or an article, for which Annex XVII contains a restriction shall not be manufactured, placed on the market or used unless it complies with the conditions of that restriction.

For items of jewellery, the specific annexes apply to anyone who supplies products which contain lead or cadmium. Also affected are articles intended to come into direct and prolonged contact with the skin and contain nickel. This includes articles such as rings, earrings, bracelets, body piercing items, necklets, chains and watch straps.


Nickel is an abundant metallic element, and is often used to create a white colour in gold jewellery. Its low cost also lends itself to being widely used in the costume jewellery industry, and is often found in plating layers.

Prolonged contact with these products may lead to nickel sensitisation, which is the most common cause of nickel contact dermatitis.

Nickel has to be present on the skin in the form of nickel ions in a solution, such as sweat. So rather than restricting the total content of nickel within the alloy, the REACH legislation sets limits for the migration of nickel from the article; 0.5 mg/cm2/week for articles intended to come into direct and prolonged contact with the skin (non-compliant below 0.88 mg/cm2/week) and 0.2 mg/cm2/week for all post piercing assemblies (non-compliant below 0.35 mg/cm2/week).

There is no correlation between how much nickel is present in the alloy and how much of it will migrate (some stainless steel watches contain up to 28% nickel but do not release enough to cause an issue). Also, the manufacturing process may alter the physical properties of the metal, so simply testing the raw material may not indicate that the finished product will pass the test.


Lead is a heavy metal that has often been used in jewellery to make the item heavier, brighten colours in paint, and to soften plastics. However, lead is also a toxic metal which accumulates in the body and even low doses can eventually lead to poisoning.

Products may not be placed on the market if any individual component of the article of jewellery contains lead equal to or greater than 0.05%. This applies to jewellery and imitation jewellery articles and hair accessories including bracelets, necklets, rings, piercing jewellery, wrist watches and bangles, brooches and cufflinks.

Certain exemptions apply, such as for crystal glass and non-synthetic precious and semi-precious stones.


Cadmium is also a harmful chemical added to alloys in small quantities to improve the functional attributes of metals or as a lead substitute. It can be present in jewellery as part of the solder, coatings or the plating process, and can also be present in the pigment of non-metallic materials.

The REACH regulation restricts the levels of cadmium in jewellery and hair accessories to 0.01%. This applies to metal components and plastic materials. The regulation also states that cadmium levels in paints and enamels need to be 0.1% or less.