Understanding 9ct, 14ct, 18ct & 24ct Gold
A practical guide to choosing the right gold for your jewellery
Gold comes in different carats, the number simply reflects how much pure gold is present in the metal. The remaining percentage is made from alloy metals such as copper, silver, zinc or palladium, which influence the hardness, colour and durability of the final piece.
Below is a simple guide to help you understand the differences, how each carat behaves over time, and why 14ct is my preferred choice for most ZOEMCBRIDE pieces.
9ct Gold - 375
In New Zealand, 9ct gold is by far the most popular. It contains 37.5% pure gold and 62.5% alloy metals, which makes it the hardest and most durable of the gold options. This is largely thanks to its high bronze (copper-heavy) content, which also gives it a more rose-y yellow tone.
Because it’s tough and affordable, 9ct is often chosen for everyday pieces. Although, that same high alloy content makes it more prone to tarnishing and discolouration over time, especially when exposed to moisture, chemicals, or skin oils and on pieces with texture or sculptural details where oxidisation naturally settles. Smooth, simple forms tend to clean up beautifully, while more intricate styles may show patina faster.
Note: In some countries, 9ct doesn’t meet the minimum requirement to be called gold, which often starts at 10ct. So if you’re exporting or purchasing overseas, keep this in mind.
14ct Gold - 585
A personal favourite. There’s something undeniably buttery about the soft glow of 14ct gold. With its 58.5% pure gold content and 41.5% alloy metals (like copper, silver, and zinc), it strikes a beautiful balance: warm in tone without being overly yellow, strong enough for everyday wear, and more accessible than the richer 18ct option. It is less prone to tarnish, especially important for textured or sculptural pieces, which keep cleaner overtime due to 14ct allow being less reactive.
For most ZOEMCBRIDE designs, 14ct simply behaves the best over time. It is the carat I most often recommend.
18ct Gold - 750
Bold, honey-like, and bright, this is gold at its most traditional and luxurious- made of 75% pure gold and 25% alloy. Because of its higher gold content, 18ct is naturally softer, making it is less suitable for very fine, delicate or intricate pieces, which can wear down faster over time but it is a delicious choice for solid, generous, sculptural forms that carry weight and presence.
24ct Gold - 999
At 99.9% gold, 24ct is as pure as it gets. It’s rarely used in fine jewellery due to its softness. While it doesn’t tarnish, it can collect dust and oils, so it needs careful handling and storage. It holds strong cultural significance and value for ceremonial or investment pieces.
A note on price and long-term value
Gold prices have steadily increased over the years. Because carat is directly tied to gold content, higher carat equals higher upfront cost but also- higher carat equals a greater proportion of pure gold, which tends to hold or increase in value over time. While jewellery should not be purchased purely as an investment, it is worth noting that 14ct and 18ct contain significantly more pure gold than 9ct, they carry more intrinsic metal value and they generally track gold price increases more noticeably over the years
If your budget allows, it can be worthwhile directing it toward a higher carat, particularly for special pieces you intend to keep long-term or pass down.
This is one of the reasons I often recommend 14ct. It offers elevated gold content and long-term value without the full price jump of 18ct.
By understanding the differences in composition, durability, and how each carat responds to everyday wear, you can select the gold that suits both your style and your lifestyle. With regular, thoughtful care, your piece, whether 9ct, 14ct or 18ct can carry its deliciousness for years to come.