About the different ring metals

The metals we offer

Most of Smooch’s rings can be supplied in yellow gold (9ct and 18ct*), white gold (9ct and 18ct*), platinum and palladium (500 & 950). Pricing information for these rings is available when you click on a ring in our ring gallery.

We can also make your ring in 14ct or 22ct gold (white and yellow), as well as titanium. These options are less popular, so we don’t include the pricing information on the site. However, please do ask your Smooch Adviser for a quote for these metals if you’re interested.

*ct = carat; more information about carats can be found in the sections below.

Smooch hallmarks

All Smooch’s rings have hallmarks – symbols stamped directly onto the metal which tell you what the metal is made of. Only the finest metals are deemed worthy of having hallmarks. Whether you buy your rings from Smooch or somewhere else, you should always check that they contain hallmarks: it’s a sure-fire way of ensuring your rings are of the quality that the salesperson says they are.

Here are the hallmarks you’ll find on Smooch’s rings – more information on what the hallmarks mean is given in the sections below.

Type of metal

Hallmark you'll find
on the ring

9ct yellow gold
9ct white gold                                                  
18ct yellow gold
18ct white gold


All the alloys

Gold is a yellow metallic element, but in its pure form it’s too soft to be used in jewellery. It therefore needs to be “alloyed” (mixed) with other metals to provide the best combination of strength, appearance and resistance to tarnishing.

The percentage of pure gold in a jewellery alloy is denoted by its carat (ct) weight. Pure gold is 24ct (i.e. 100%); Smooch provides 18ct and 9ct yellow gold and white gold. 9ct is the harder alloy and can scratch softer carat weights. For this reason it’s a good idea for your wedding ring and engagement ring to be the same carat weight.

Be aware though that even if you wear the same carat weight of gold, it’s still likely to scratch and wear down over time. This is because gold isn’t very durable – especially compared to other jewellery metals like platinum and palladium.

Please note that gold, just like all precious metals, does scratch as soon as it comes into contact with any hard surface.

All gold starts out as yellow gold. The only difference between yellow gold and white gold is the other metals that it’s alloyed with. Yellow gold is often alloyed with a mixture of silver, copper and zinc. White gold on the other hand is a mixture of yellow gold and at least one white metal.

Does white gold turn yellow?

Some people find that their white gold jewellery yellows. This happens when low-quality alloys have been used. Smooch’s 18ct white gold rings contain a high proportion of palladium – a high-quality alloy. (Palladium can also be used as the main metal for jewellery these days – see below for more information.)

Unfortunately, 9ct white gold doesn’t contain any palladium because manufacturers believe it would increase the price too much for people who want a less expensive ring. This means that it’s likely to develop a yellowish tinge within a matter of months.

All jewellery makers plate their white gold jewellery with rhodium – a beautiful and very rare metal – which gives the gold a brilliant white finish. This is just a plating, however, and it will wear away. Smooch will resurface your white gold ring at any time you want, free of charge.(except for a polish and insurance charge) It’s all part of our Lifetime Guarantee.

Has your ring had past lives?

Gold is probably the most recycled metal in use today, and some industry specialists estimate that about 85% of the gold used in jewellery contains a percentage of recycled (“eco”) gold. You’ll see from the table below that your ring will contain a certain amount of this recycled gold. Because gold can be recycled many times over, it’s entirely possible that your ring contains gold that was mined hundreds of years ago and has been used in jewellery during the time of the Pharaohs, the Roman Empire and the Middle Ages.

Smooch’s gold rings and hallmarks

The table below gives more information about the alloys of our gold. The number in brackets in the “Type of gold” column is stamped onto the jewellery; this is the hallmark that indicates the percentage of pure gold (e.g. 9ct yellow gold will be stamped with “375” – 37.5% pure gold).

Type of gold

Alloy mixture

9ct yellow gold (375)

37.5% fine gold (including a proportion of recycled “eco” gold)

10.3% silver
The remainder is a mixture of copper and zinc.                           

9ct white gold (375)                                                 

37.5% fine gold (including a proportion of recycled “eco” gold)
44.5% silver
10% copper
8% zinc                                                                                                  

18ct yellow gold (750)

75% fine gold (including a proportion of recycled “eco” gold)
15.97% silver
8.93% copper                                                                                      

18ct white gold (750)

75% fine gold (including a proportion of recycled “eco” gold)
15% palladium
10% copper


Interesting facts about gold

  • The stuff is pretty malleable: a single ounce can be beaten into a sheet of 300 square feet.Interesting facts about gold
  • Gold doesn’t rust or corrode.
  • One cubic foot of gold weighs more than half a ton.
  • The largest nugget of gold was found in Australia in 1869; it weighed 172lbs.
  • Gold was first used in jewellery in 4,000 BC (approximately).
  • At the end of 2009, it was estimated that the total amount of gold mined since man first appeared on earth is less than 165,000 tonnes; that would take up the same space as 60 double-decker buses if all gathered together in one place.


Platinum is a wonderful and popular choice of metal for wedding rings. If you prefer white-coloured rings, then platinum could well be the perfect choice for you.

Unlike white gold, platinum is naturally “white” (silvery-grey) and it never discolours. Platinum does scratch (giving the metal a greyish tinge after a few years), but these scratches can be polished off completely using specialist equipment. Smooch’s Lifetime Guarantee means that you can send us your platinum wedding rings at any time for a good old polish, returning them to their first-bought beauty.

Platinum is also extremely strong – it’s the strongest of all the jewellery-making metals – and is therefore ideal for setting stones. It’s also very dense and remarkably heavy – much heavier than silver or gold. Please note that Platinum like all precious metals does scratch, as soon as it comes into contact with any hard surface.

There’s more! Platinum is also hypoallergenic, making it a good choice for people with sensitive skin.

Because platinum is so strong, it can be used at 95% purity (because it doesn’t need to be alloyed – or mixed – with other, stronger metals, like gold does). Our platinum is alloyed with 5% ruthenium.

The platinum hallmark

As with gold, you’ll find a hallmark number stamped on your ring to indicate that it’s made from platinum. It will say “950”, because the ring is made from 95% pure platinum.

Interesting facts about platinum

  • Although there is ever so slightly more platinum on the earth than gold (0.005 parts per million of the earth’s crust is platinum, whereas 0.004 parts per million is gold), it’s harder to mine. There are two reasons why it’s harder to mine: 1) platinum is widely dispersed and in very small particles; 2) it is so often attached to other metals, and expensive equipment is needed to separate them and refine the platinum. As a result of being harder to mine, less is produced and it’s therefore more expensive.
  • All the platinum ever mined would fit into a typical living room. (The size of this living room has never been quoted, but we’re assuming it’s smaller than the Queen’s.)
  • Platinum is the least reactive metal in the periodic table. (But before you have a smug “my metal is less reactive than your metal” moment with a gold-wearing friend, be aware that gold comes a close second in the least-reactive list.) 
  • The only material suitable for the electrode in cardiac pacemakers is platinum.
  • Because it’s such a strong and dense metal, it’s used in many items other than jewellery – catalytic converters, laboratory equipment, electrodes, medical/dentistry equipment and more. It’s also used for military purposes. In fact, during World War II the US Government declared platinum a strategic metal and banned its use in non-military equipment – including jewellery.


Palladium is becoming increasingly popular for use in wedding rings today, because it has properties similar to that of platinum but is far cheaper. In fact, palladium is a member of the platinum family (which consists of six metals with very similar properties to each other). 

Like platinum, it’s naturally white (silvery-grey) in colour. Also like platinum, it’s great for diamond setting and is a tough, strong metal. It’s also hypoallergenic, making it a great choice for people with sensitive skin. This metal is about 40% lighter than platinum, but it’s also about 50% less expensive.

The reason palladium is so much cheaper than platinum is because – although it’s also very rare –it’s easier to mine: its low melting temperature means that it’s easy to separate it from other elements that it’s attached to. The low melting temperature means that it’s also easier to shape into jewellery than platinum.

While palladium has always been used for technical purposes (e.g. machinery), it wasn’t ever malleable enough to be shaped into jewellery. In the 1930s however, new palladium alloys were created which made it possible for shaping, casting and moulding into jewellery.

Smooch offer two types of Palladium. Palladium 500 contains 50% Palladium. Palladium 950 contains 95% palladium alloyed with 5% ruthenium.

Please note that Palladium, like all precious metals does scratch as soon as it comes into contact with any hard surface.

The palladium hallmark

As with gold and platinum, you’ll find a hallmark number stamped on your ring to indicate that it’s made from palladium. It will say either "500" meaning the ring will contain 50% Palladium or “950” meaning the ring contains 95% Palladium. Rings made from Palladium 500 are slightly darker than rings made from Palladium 950.

You might have noticed that both platinum and palladium are stamped with “950”. So how to tell which is which? Simple! Just look at the shape of the hallmark – you’ll know it’s palladium if it looks like either of these two shapes:

Interesting facts about palladium

  • In the late 1800s, palladium was more expensive than platinum.
  • Palladium was named after the asteroid Pallas, which was discovered two years before the metal in 1801.
  • Palladium can absorb nearly 900 times its own volume of hydrogen gas. During the process, the metal visibly expands – like a sponge does when it absorbs water. Because palladium has this property, palladium filtration is a common method of removing impurities from hydrogen gas.