What's the difference between 9ct and 18ct gold?

What's the difference between 9ct and 18ct gold?

We love weddings

Champagne, canapés and big smiles all round. What's not to love? Your wedding day can be as extravagant or simple as you like. Whether you have a hundred guests or no guests at all, it's sure to be a day you'll never forget. 

One of the most obvious daily reminders of your nuptials if your wedding ring. You're going to wear it forever, so it's pretty important to choose carefully. If you've fallen in love with our Forever Ring design, but don't know which carat gold to pick, this article is for you. 

What's a carat?

First of all, let's learn the lingo. 'Carat' is often abbreviated to 'ct' or 'k', but it all means the same thing and has nothing to do with root vegetables. The 'carat' refers to the percentage of pure gold in the alloy. The key difference between 9ct and 18ct gold is this percentage of pure gold. For 9ct it's 37.5% and 18ct it's 75% pure gold. 

Why mix the gold?

Pure gold is too soft to be used in making jewellery, so it's usually mixed with other metals to make it stronger and more durable. Sometimes metals are also mixed in to alter the colour, which how white gold and rose gold are created. 

Will gold tarnish?

Pure gold is one of the least reactive elements in the periodic table. However, the other metals that are mixed in to make the gold usable in jewellery are much more reactive and prone to tarnishing. Because 9ct gold contains a high percentage of these other metals, it's more likely to suffer from discolouring or tarnishing if you wear it in the pool, or spray it with perfume, for example.

So if you choose a 9ct gold ring, be prepared to protect it from everyday chemicals. 

Is 9ct or 18ct gold more durable? 

When it comes to strength and durability, 18ct gold is going to win every time.

Are you ready for a little more science? OK, here goes. Remember that 9ct gold is mixed with a larger percentage of other metals (62.5%) compared to 18ct gold (25%)? You might think this would make 9ct gold stronger, but you'd be wrong. These other metals actually result in 9ct being less dense that 18ct gold, which means it's less durable and can wear away over time. So if you want a ring that's more resistant to damage, scuffing and wear, you'll want to choose an 18ct gold ring. 

Ready to choose?

The Forever Ring is our take on the classic gold band, complete with our signature textured finish. Created for wild souls, inspired by the organic world around us. So that we can craft the perfect piece for you, every Forever Ring is handmade to order using certified recycled gold. As it's made just for you, we can add more or less texture to suit your style. 

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