Wednesday 9 October 2013

Metal in Jewellery

I promised yesterday that I'd go into a bit more detail. This won't be too advanced, so don't worry, but I do ask you to just have a quick look at this, a chart you may remember from school.


You can click on it for a better look, but briefly, all the orange and light blue squares are metals, as are some of the others. There are a LOT of metals, in fact most elements that occur naturally are metals.

But for the sake of this article we don't need to worry about many of them. They simply are not used in the jewellery industry, or so rarely that you are unlikely to come across them.

When people think of jewellery they usually think of two groups. The first is precious metals (silver, gold, platinum, rhodium, and palladium). They are precious because they are rare, and consequently expensive. Wars have been fought over silver and gold, and many lives lost.

Gold stays shiny and bright without tarnish for centuries (forever, pretty much), and it was this property that first attracted us to it. Silver, on the other hand, tarnishes quickly and is less valuable but still extremely important and desirable.

Beginning way back, jewellery has also been made from other metals often known as base metals; this is our second group. These include copper, iron, and tin. The term "base metal" is a bit of a misnomer as it properly only refers to metals that react with hydrochloric acid, but it's used informally to describe the common metals that are not precious.

Early in human history we discovered that two or more metals can be mixed together to create alloys that have the best properties of each. You may have heard of the Bronze Age......

Bronze was initially made from copper and arsenic, and subsequently copper and tin, and was a revolution, being harder than either of them and incredibly useful for just about everything. Weapons, jewellery, and some of the earliest construction hardware were made from bronze, and when it was discovered that it stood up to saltwater, it was guaranteed a place in our seafaring world long after iron and steel had replaced it for other uses.

Today bronze often includes silicon or aluminum, and other mixtures such as copper and zinc have been used for a long time. Indeed many other metals, sometimes more than one, have been added to copper to create bronze. It's therefore not a strict recipe. This is important to understand, because questions such as "What is bronze made from" really have no single answer.

Which brings me to today's costume jewellery alloys. The debate still rages over these, despite many reassurances from manufacturers that toxic metals are not included and I've dealt with that separately in an earlier blog. Some of the fuss is pure snobbery. Silversmiths look down their noses at costume jewellery, especially if it's mass produced. I believe if you like a thing, you like it, and everything has its place.

The simple fact is, the superiority of a metal is relative to its purpose. For an heirloom piece it makes sense to use a precious metal. For everyday fashion jewellery it does not. Many of the modern alloys retain their looks without cleaning, and busy people do not want to be forever attending to the oxidization of their jewellery. If you want a valuable item, that you can resell later if need be, then certainly, buy gold. But if you just want something you can discard at whim as the fashion changes or you bore of it, it makes absolutely no sense to spend large amounts.

A greater concern, surely, is allergies. It is the inclusion of nickel that is the usual problem. While it is still widely used, public demand seems to be affecting that quite powerfully. Some countries even restrict the use of nickel. Manufacturers in the Far East really have no choice but to follow this demand if they are to stay in business, so increasingly nickel is found less and less in jewellery, restricted to the cheapest end of the market.

So what is your costume or fashion jewellery made from?

There are several types. Very light jewllery is often made from aluminum, or an aluminum alloy (with silicon, etc). Although there is talk of world shortage, and consequently it's not as cheap as it once was, there is plenty of it on the market. Aluminum is very easy to colour by anodizing and it doesn't tarnish. We have tested anodized aluminum inadvertantly by losing it under a pile of snow for months. It didn't change at all. If you want a real carefree material, this is your first choice.

However, this light weight can put some people off. The look and feel of the heavier alloys is desirable and this is the reason that plated metals are so popular.

It surprises many people that many components of plated costume jewellery are often iron, with a reasonably thick plating of a more resiliant alloy, or a light plating of silver, or sometimes even gold. It's not hard to discover which pieces have iron at the centre as they are magnetic. If the plating is good, these are perfectly serviceable for some time, and vintage pieces are easily found on the market dating back many decades.

Slightly upscale the central core could be brass. I've had many people tell me their bass based components are finer as they are not magnetic, as if iron is somehow a "poor" metal to use, but just as the rust can break through the best plating if an item is allowed to get damp, green corrosion can occur on brass based items under damp conditions just as quickly. The answer is to keep it dry.

Brass itself is similar to bronze, but is usually a mixture of copper and zinc. There is a lot of overlap here though, and the distinction between bronze and brass can be arguable.

For that reason modern bronze jewellery is often "actually" brass, but with other additives to enrich the colour, so it's really strictly neither one nor the other. As I stated earlier there is a lot of variation in alloys, both in composition and ratio, and it's hard to pin definitions down.

The most popular alloys on the market today are the zinc based, antique silver coloured pieces known frequently as Tibetan silver or "silvertone". Once upon a time there was a silver alloy made in Tibet, and there still is, in very small amounts. The vast majority of Tibetan silver on the market today contains little or no actual silver (except sometimes as a plating) and the name is simply a convenient trade description.

Zinc and what then? This varies a lot. Like pewter, which is very similar, it can have a number of ingredients, and one of them was typically lead. Due to public demand this has been removed from the recipe by most manufacturers. Copper is less common these days as prices rise, although the weight of many pieces makes its presence felt, and increasingly nickel is being replaced by iron, to prevent allergic reaction. Therefore your magnet test may well pick these up. But there is no hard and fast rule, and most observers believe the metals used are at least partially decided by price and availibility.

The benefits of these modern alloys are obvious. They are both inexpensive and easy-care. So long as you don't store them in damp conditions they will last for decades, even long after you lose interest in them. If the design is timeless they can become favourites just as easily as expensive pieces. I have been making costume jewellery since 1991, and pieces my friends had at that time are still being enjoyed. This isn't throwaway jewellery.

There is a tremendous difference between the quality of mass produced fashion jewellery, and carefully hand-made costume jewellery. In fact, I may be accused of bias, but I would go so far as to say that the care and attention to detail in small scale production costume jewellery makes it superior than mass produced mall jeweller "fine" jewellery. Quite apart from anything else, the uniqueness of the piece beats "everybody has one" of the mall jewellers' sterling trinkets, hands down.

I'll just touch briefly on two other metals you may come across, titanium and niobium. These have become extremely popular in recent years for their zero allergy reputation, and the effect anodizing has on them. An electric current will change the surface colour depending on voltage. Titanium has spectacular, bright, almost garish colours, while niobium is more subtle. Neither will tarnish and consequently they are increasingly being thought of as an alternative to precious metals.

Stainless steel and surgical steel are often considered good choices, for appearance and durability, but they are very hard to cut, which is part of the reason for higher prices. Still, they have nice bright finish, which like the other alloys, requires little attention.

Finally, tungsten carbide (not an alloy, but a chemical compound, only the tungsten being metal) has taken the market by storm for it's hardness and durability, which surpasses that of gold. The downside being, if it is broken, it's not repairable.

When you choose a metal the important things to consider are:

How often will I wear this?
How much do I want to spend?
What "look" am I aiming for?

The three often have to be juggled a bit.

You know my mantra by now...jewellery is to be enjoyed. Its value is in its appearance. Although we have spot prices on gold these days, it is not truly worth anything unless people want it. Beauty is in the eye of the beholder. That's you. Buy what you LIKE.

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