Have you ever wondered what the difference is between a carrot and a carat, or what makes platinum better than silver? The world of jewellery can be bewildering if your only involvement with it is admiring and wearing beautiful pieces. There is always plenty of terminology and jargon to familiarise yourself with, certain things to look out for and avoid, and a vast array of precious metals, gemstones, styles and settings to choose from.
In the Claddagh Design workshop we work with all types of precious metals such as gold, silver platinum and palladium. So we decided to take it upon ourselves to explain all of the most common things that confuse people about jewellery.
A precious metal is metal that is naturally present, rare, and has high economic value. When most people hear the phrase, they automatically think of gold and silver. While both are of course classified as precious metals, there are also many other types, as well as several variations of each type. Some other lesser known precious metals include:
Platinum – Found primarily in South Africa, Russia and Canada, platinum has similar qualities to silver such as its remarkable resistance, lustrous look and high density. It is non-corrosive and extremely malleable, and as well as jewellery is used in dentistry, weaponry and aeronautics.
Palladium – Palladium has a grey-white colour and is valued for its stability under extreme heat and ability to absorb high levels of hydrogen at room temperature. It is regularly used in catalytic converters in motor vehicles, while jewellery makers use it to create white gold alloys.
Rhodium – This extremely rare metal is silver in colour, has an impressively high melting point (1963 degrees celsius) and is also highly reflective. For this reason it is commonly used in search lights, mirrors, jewellery finishes and several industrial fields.
Osmium – Osmium is one of the densest elements on the planet, and is also a very hard and brittle metal. It is silver wit blue-ish tinges, is found in Russia and both North and South America,and is used to harden platinum alloys for electrical contacts and filaments, amongst other things.
Rhenium – This is a rarely found metal, the biggest reserves being in Chile, Kazakhstan and the United States. It is another one of the densest elements and has the third highest melting point of any metal. It is used in high temperature turbine engines and nickel-based alloys to improve temperature strength.
Indium – This metal is found in China, South Korea and Japan and is produced from zinc, lead, iron and copper ores. In its purest form it is white in colour and is very shiny and malleable.
Over time as mining technology improves and more deposits of certain metals are found, they go from precious to common. One excellent example is aluminum, which went from being a rarely discovered metal to being used in everything from food cans to tinfoil in just a few decades.
Gold is one a unique precious metals as it is one of the few that is not silver, grey or white in colour. Since the beginnings of recorded history it has been highly valued and used in art, jewellery and as currency. It is another very malleable metal and is non-reactive with other metals. Most of the gold naturally occurring in earth lies at its core, however, gold (as well as many other precious metals) is generally believed to have been deposited by meteorites that landed on the planet billions of years ago.
The Vredefort crater, for example, was the result of a meteorite impact and is credited with seeding the Witwatersrand basin in South Africa with one of the richest gold deposits on the planet. Although in this case, the gold deposit was already present beneath the crater, covered in lava.
A 'carat' refers to the gold content of the metal. The bigger the carat, the more gold is mixed with other metals to create the alloy that is the final metal, and therefore the more expensive the piece will be. Gold normally comes in carats of 9, 12, 18 and 24. In the case of 9 carat gold it is 37.5% pure gold, while 18 carat is 75% pure gold. The remaining 25% is made of different metals which serve to harden the alloy and make it more durable and longer lasting. We use 9ct gold in our designs but really you can have any of our jewellery made up in whatever carat gold you would like.
So how does white gold, rose gold and yellow gold come to exist? This is where the other metals in the alloy come in. Yellow gold is made by mixing pure gold with copper and zinc. Rose gold is made with extra copper in the alloy, giving it its red-pink hue. White gold is a mixture of gold, silver, palladium and small amounts of other silver or white coloured metals. White gold is also often coated with rhodium for extra shine and reflectiveness, and whiteness. Believe it or not, other colours such as blue gold, black gold, purple gold and green gold do also exist.
Silver may not be as valuable as gold or platinum, but it still has a lot going for it. It has the highest electrical and thermal conductivity of all metals, is one of the most reflective metals, and also has the lowest contact resistance of any metal too. It is used in everything from money to photography, and although we may be biased, it makes some very beautiful jewellery too!
Like gold, there are several different type of silver, although they refer to the purity rather than the colour of silver and are classified by names rather than carats. The most common type (and they type we use for our designs) is Sterling silver, which is an alloy of 92.5% silver and 7.5% copper (and sometimes other metals such as nickel). Other types of silver are named based on their origin. Britannia silver is 95.84% pure, and was the standard in England until 1697. Alpaca silver is an alloy of copper, iron and zinc... it's not actually silver at all! The same is true of Nickel or German silver, which is a similar alloy with differing proportions of the same metals.
Contrary to silver and gold, platinum is used in the most pure form possible for jewellery. While silver and gold are very malleable metals and need to be mixed with others to make them hard wearing, platinum is naturally so. For this reason, it is heavier and of course more expensive than either of its counterparts; and 18 carat platinum will cost at least twice the price of a gold one. Usually platinum just comes in different carats rather than different colours of types. Platinum jewellery is extremely long lasting and does not tarnish, so very little maintenance is necessary. It is often used in engagement and wedding rings but we can make any of our designs in platinum. We also make our Ogham weddings rings in platinum like the pair pictured here.
Bronze is an alloy made mostly from copper, but the other metals used (usually tin) make it much harder than copper. It was a favourite of ancient societies as it was readily available and very easy to work with. People used it to create tools, art, jewellery and various other artifacts. The earliest bronze objects known date from 4500BC, and thanks to the metals durability, many have survived more or less intact to this day. 'Modern' bronze is 88% copper and 12% tin.
Bronze is classified by the type of particular type of alloy used to create it. In the Bronze Age, 'classic' bronze contained 10% tin, 90% copper and was used for casting, while 'mild' bronze contained just 6% tin and was hammered from ingots to make sheets. Classic bronze was used for heavier items like bladed weapons, while mild bronze was used for more lightweight objects like helmets and armour. Today the main types are Bismuth bronze, which is 52% copper, 30% nickel, 12% zinc, 5% lead and 1% bismuth. Plastic bronze contains lead to improve plasticity. Architectural bronze (bet you can't guess what it's used for!) is 57% copper, 3% lead and 40% zinc.
Before stainless steel came along, bronze was regularly used for boats and ships due to its resistance to salt water corrosion, and still is used for certain submerged parts. It is also the metal of choice for bells, cymbals, and musical instrument strings as it gives a near perfect durability and timbre balance. Of course, bronze also has one other specific usage; medals! This tradition dates back to the Olympic Games of 1904, when the top three competitors of each sport were given gold silver and bronze medals to represent the first three ages of man in Greek mythology.
The value of different precious metals varies greatly from year to year, largely depending on supply and demand. Gold is not as affected by this as other metals, as the amount of above ground gold already in use is much greater than what has been left of un-mined gold. Since gold can me melted down and recast very easily, there isn't as great a need for a constant stream of 'fresh' gold. However, what does affect gold prices is the amount of buying and selling of this hoarded gold. When there is a trend for buying, new supply is needed and the price goes up.
Silver, on the other hand, has enormous value for a whole range of industrial uses, so prices fluctuate a lot. Whenever new innovations in certain technologies come along, you can be sure the price of silver will change. For example, silver was used for decades in photography and was very much in demand, until the digital camera came along and photographic film was rendered more or less obsolete. Its value is usually quite close to that of gold regardless.
Platinum always gets a higher price than both silver and gold because it is much, much rarer. This is especially true during times of market and political stability. Like silver, it is also considered an industrial metal and is specifically used in the automobile industry. Therefore its price is often affected by the sales and production numbers of vehicles. It is also only found (so far) in South Africa and Russia, driving the price up even higher. I'll finish with an interesting fact about platinum. If you took all the platinum mined in the world and put it in an Olympic size swimming pool it would only come up to your ankles!!