The most popular choice for engagement rings is 14k gold. This gold alloy has a higher percentage of pure gold and a lower percentage of other metals, which makes it more affordable and less prone to tarnishing. 14k is the most common type of gold used in jewellery and is often used in wedding bands as well. When you compare 14k to 18k, the difference isn't always visible. However, when you look at the colour of each ring side by side, you can see that 18k appears richer and yellower than 14k does.