Choosing between gold and platinum
Fine jewellery is typically crafted from either gold or platinum. But what are the differences between platinum and gold, and which is the right choice for your engagement and wedding rings? On the one hand, gold is the 'original' precious metal of choice, whose beauty and value have been coveted for thousands of years. On the other, platinum is even rarer and more valuable than gold and has gained a certain caché as the most luxurious of the precious metals in more recent years.
What is platinum?
Platinum is a silverish-white precious metal with the atomic number 78 and the chemical symbol Pt. It is a very dense metal at 21.5 grams per cubic centimetre.
Platinum is 30 times rarer than gold. Indeed, it is said that if all the platinum ever mined were poured into an olympic-size swimming pool, the top of the metal would barely reach your ankles!
Although platinum has been used to make fine jewellery since the late 19th century, in the UK, it was not until 1975 that the new Hallmarking Act introduced the requirement that all articles over 0.5 grams be hallmarked.
Platinum gives its name to a family of six metals (platinum, palladium, rhodium, ruthenium, osmium, and iridium) known as the platinum-group metals.
Platinum is too soft in its pure form to be used to make jewellery. For this reason, it is alloyed (mixed) with other metals to make it harder wearing and better for jewellers to work with. In fact, it is other platinum group metals that platinum is most commonly alloyed with.
Recognised international standard "finenesses" (purity levels) for platinum are 850, 900,950 and 999 parts per thousand, though, in the UK, platinum 950 is the form used almost ubiquitously for jewellery. Platinum 950 is 95% platinum by weight and 5% alloy. The UK hallmarks for platinum reflect the fineness of the metal, so the vast majority of platinum jewellery in the UK is stamped with "950".
In addition to being used as platinum alloys, two platinum-group metals are widely used in jewellery. Palladium is sometimes used as a lighter-weight alternative to platinum but is more commonly used as an alloy in the production of white gold. Meanwhile, rhodium is widely used to plate white gold to make it look more like platinum! Historically, platinum has been more expensive than gold, so jewellers introduced white gold as a lower-cost alternative for their customers.
What is gold?
Gold is a bright, slightly orange-yellow precious metal with the atomic number 79 and the chemical symbol Au. Gold is a very dense metal at 19.3 grams per cubic centimetre (though less dense than platinum). Like platinum, gold is too soft in its pure form to be used to make jewellery and is therefore alloyed with other metals - most commonly silver, copper and palladium.
Pure gold is known as 24-carat or 24ct gold, but most gold jewellery in the UK is made with either 9ct gold or 18ct gold. 9ct gold is nine parts gold out of 24 (37.5% pure) and is more commonly used for fashion jewellery. Fine jewellery is more often made with 18ct gold, which is 18 parts gold out of 24 (75% pure).
The hallmark for 9ct gold is 375 (reflecting that it is 375 parts gold per thousand), and the hallmark for 18ct gold is 750 (750 parts gold per thousand).
The alloys that gold is mixed with not only make it harder but can also be used to change its colour.
White gold vs platinum
One of the most common dilemmas faced by a client choosing a ring is whether to go with white gold or platinum. If you find yourself in that position, there are a few useful facts to bear in mind.
White gold is created by alloying gold with white metals such as silver and palladium. In addition, most white gold jewellery is plated with rhodium, a naturally white metal from the platinum group. It is the rhodium plating that gives white gold its bright-white appearance. Unplated white gold tends to have a slightly warmer tone. Over time, rhodium plating can wear away, and the warmer tone of the white gold will show through, at which point you may wish to get your white gold jewellery replated.
Platinum, in its unpolished state, is a pale grey colour, but when it's highly polished becomes so reflective that it takes on a bright white appearance. In contrast, white gold is a slightly off-white colour, retaining a hint of yellow even when polished, unless it is rhodium-plated (which most white gold is), in which case it takes on an even brighter white than platinum. The image below is of four 18ct white gold rings. Two are rhodium-plated (one polished and one matte), and two are unplated (again, one polished and one matte).
Comparison of platinum and gold
Colour and appearance
The most obvious starting point when considering the differences between gold and platinum is their colour. Whereas gold is yellow in its pure form, platinum is a white metal. But gold is also widely available as rose gold and white gold, meaning that jewellery buyers have at least four main options to choose from for their precious metal.
Platinum and white gold look very similar, but a slight difference is discernible on close examination. Most white gold is rhodium plated, which has a slightly lighter tone than platinum, whereas unplated white gold has a slightly warmer tone.
Both platinum and gold are commonly polished to produce a bright, lustrous finish, although it is also possible to achieve satin and matte finishes through brushing or sandblasting.
Historically, platinum jewellery has always been more expensive than gold jewellery. However, the prices of these two different precious metals move up and down with supply and demand, driven in part by the jewellery market but also by financial markets, and so the gap in price between them narrows and widens at different times.
Platinum rings have a particularly luxurious feel and aesthetic primarily due to their weight! Not only is platinum more dense than gold, but platinum 950 is 95% pure, whereas 18ct gold is 75% pure. These two factors combine to result in a platinum ring weighing approximately twice as much as a gold ring of the same size.
In practical terms, one of the most important differences to be aware of is malleability, with platinum being less malleable than gold. This means that platinum stands up better to wear and tear over the long term and is very well suited to creating more delicate designs. Platinum settings are also more secure than the same settings in gold. However, platinum's lack of malleability can be problematic if you want to set a softer gemstone like emerald, where the force needed to create a platinum setting could damage the stone. In this situation, white gold may well be preferable.
Wedding and engagement rings are inevitably subjected to significant wear and tear due to being worn daily. This is particularly noticeable on the underside of rings, where they come into regular contact with hard objects like door handles.
Being more durable than gold, platinum rings tend to be less prone to damage than gold rings. The likelihood of needing a platinum ring reshaped or the prongs retipped is less than it is with gold.
In addition, if you have a white gold ring that has been rhodium-plated, as the rhodium gets scuffed and scratched away, it will eventually start to reveal the natural warmer colour of the white gold underneath. Every few years, the ring will need to be repolished and replated if you want it to look bright white again.
However, that is not to say that platinum is completely maintenance-free. Despite platinum's very high tensile strength, it marks relatively easily, forming what is known as a 'patina' of tiny scratches on its surface. After a while, platinum will lose its brightly polished finish, taking on a greyer colour, and will need to be repolished every few years if you want it to look pristine. And unlike gold, where a tiny amount of metal is lost every time you polish it, platinum is not worn away by polishing. You can polish it as much as you like without any loss of metal.
Alloys and hallmarks
Both gold and platinum are alloyed to make them more hardwearing since they are too soft to be used for jewellery in their pure forms. This alloying can also be used to create different colours of gold. Mixing gold with silver and copper retains a yellow colour; mixing it only with copper creates the pink colour of rose gold; mixing it with silver and palladium produces white gold.
Pure gold, or fine gold as it is called in the industry, is also known as 24ct gold. In the UK, the gold used in fine jewellery is most commonly alloyed to 18ct (18 parts out of 24, meaning 75% purity). In different countries, other standards have been adopted. In the US, for example, 14-carat gold is very popular (58.3% purity). The UK hallmark for 18ct gold is '750', signifying 750 parts gold out of 1000.
Platinum, on the other hand, is typically alloyed to 95% purity in the UK (the other 5% is usually ruthenium or cobalt), for which the hallmark is '950' hallmark, signifying 950 parts platinum out of 1000.
How do I stop my platinum ring from getting scratched?
Platinum is easier to scratch than gold, so you should be more careful under which conditions you wear your ring. Avoid wearing platinum (or any precious metal) when doing physical activities.
I'm having my ring engraved; should I choose gold or platinum?
Both gold and platinum rings can be engraved, so this shouldn't be a factor in choosing between these precious metals.
Is platinum more expensive than gold?
Historically, platinum jewellery has tended to be more expensive than gold due to a combination of differences in scarcity, density and purity. Platinum's scarcity means that pure platinum tends to cost more per gram than pure gold, while its density means that more grams are required to make the same piece of jewellery in platinum than in gold. And finally, the platinum in jewellery tends to be 95% pure, whereas gold jewellery is rarely more than 75% pure.
Platinum and gold are the most famous precious metals in fine jewellery and are widely used to make engagement rings and wedding bands.
Gold is available in three main colours (yellow, white or rose), but platinum is only available as a white metal. When choosing between white gold and platinum, platinum is excellent for those who prefer a heavier ring and is more durable than gold. White gold needs to be replated every few years, whereas platinum may need to be repolished more frequently than gold.
Platinum jewellery is usually more expensive than gold jewellery, but whichever precious metal you decide on, you can rest assured that both gold and platinum are excellent choices for engagement rings and wedding rings.
At Ingle & Rhode, we have a collection of rose gold, white gold, yellow gold and platinum engagement rings. Please feel free to get in touch if you'd like more advice on the best precious metal option for you or visit us in person at our London showroom near Bond Street station. We'd be delighted to help.