I usually use nickel-free 18 karat or white gold plated brass ear wires and posts to complete my earring designs. This gives a good quality, cost-effective finish to my work that is wearable by most people. However, if earrings make your earlobes itch or your necklace leaves a rash around your neck, you may have a nickel allergy. It’s one of the most common skin allergies.
If you do have a nickel allergy, jewellery made of surgical-grade stainless steel or either 14, 18 or 24 karat yellow gold may provide some relief. Other nickel-free metals include pure sterling silver, copper, platinum, and titanium.
Precious metals including gold, silver, platinum and rhodium are used in jewellery making because they are relatively rare and therefore more valuable and highly desired.
Gold is a favourite for jewellery making. An excellent conductor of electricity, it is very non-reactive with air, water and most other substances, meaning it won’t corrode or tarnish. This is generally true of karat golds as well, as long as the gold content is high enough, i.e. about 18 karats.
Because pure gold is soft, it is often alloyed with other metals to give it strength. A karat refers to the amount of pure gold in the gold, with 24 karats being 100% pure gold. 14K indicates a product that is about 58% pure gold, and most commercial gold jewellery is 14K to 18K. The remaining parts are usually silver, copper, or another metal. What the gold is mixed with will affect its colour – rose, yellow or white.
Pure gold is yellow in colour. Rose gold, also known as pink gold and red gold, is a gold and copper alloy widely used for jewellery. The alloys commonly used in white gold are gold, palladium, and silver, with palladium acting as a bleaching agent for gold. Nickel used in some white gold alloys and can cause an allergic reaction. Because of this, many countries do not use nickel in their white gold formulations.
In jewellery making, ‘plate’ is a very thin layer of gold or silver which is electroplated or electrochemically applied to another cheaper metal, usually brass. It is about 1/1,000 of an inch thick.
Gold ‘filled’ refers to a layer of gold or silver applied to a cheaper metal with heat and pressure, and it is up to 100,000 times thicker than regular plating.
Something referred to as gold or silver finished consists of a base metal that has been electroplated with a non-standardized thickness of gold or silver.
Sterling silver is another favourite of jewellery makers. It consists of an alloy of at least 92.5% silver and another metal, usually copper. Because of this, sterling silver will tarnish over time, and will have to be cleaned periodically unless an antiqued look is desired. Fine silver (99.9%) is generally too soft for producing functional objects, so the silver is usually alloyed with copper to give it strength.
Platinum is a very hard silvery-white metal that is resistant to corrosion, wear and tarnish. Because it is more rare, it is more precious (and expensive) than silver or gold.
Rhodium is a very hard silvery-white metal that is closely related to platinum, but is liquid in its raw state. Because of this, it can be applied to base or precious metals to give them a platinum-like appearance that resists tarnishing.
A base metal is any metal that is not precious. Common examples used in jewellery include copper, brass and nickel. Brass is an alloy of 70% copper and 30% zinc. Copper is a soft metal that is not very durable. Many findings are copper-plated rather than pure copper for strength.
Gunmetal is a dark coloured antiqued brass. Pewter is an alloy of tin and various amounts of antimony and copper. Genuine pewter contains lead, but lead-free pewter is available.
Stainless steel contains more than 10% chromium and may contain nickel, titanium, niobium and other elements. Stainless steel is considered hypo-allergenic and does not rust. Items like stainless steel that are called nickel free are still allowed to contain a very small amount of nickel!
Niobium is a hypo-allergenic metal that is usually anodized into a range of colours, and most metal-sensitive people can wear it. Titanium is a lightweight metal that can also be anodized into a range of colours, and can be worn by most with metal sensitivities.
So, for those who do suffer from metal sensitivities, some good options are niobium, titanium, sterling silver, 14K gold, or plastic.