Both 9ct and 18ct gold have their benefits and drawbacks. Let us give you a little more info on both metals, so if you're deciding between 9 or 18 you have all the information you need.
Firstly, if you want to brush up on what Carats are, check out our blog post here.
Price is the first factor to think about when choosing between 9ct and 18ct. Obviously, the higher the gold content, the more expensive the gold will be. If your budget allows for 18ct gold, we almost always recommend it, but 9ct is still a lovely option for many pieces that will last a lifetime if treated well.
The second factor that many people want to know about is the appearance of the metal. 9ct gold is gold which has 9 out of 24 parts gold and 15 parts of another metal (usually copper, zinc, silver, palladium or platinum). 18ct gold has 18 out of 24 parts gold and 6 parts of other metal. For yellow gold, the higher the gold content, the yellower the metal will appear. 9ct has a lovely soft and buttery colour, whereas 18ct has a brighter and warmer tone.
This is the same for both 9ct and 18ct rose gold, but the only difference is that the gold is mixed with more copper to give the warm, pink colour. White gold is a little different, and contains silver, palladium and platinum to give it the cooler and lighter colour. A white gold with less platinum and palladium has a slightly warmer and yellower colour than those with more.
The next factor to consider is durability. You may have heard that 9ct gold is a "harder" metal, as gold is quite soft, it makes sense that more other metals create a stronger metal overall. But this is a confusing misconception. While 9ct is technically "harder" it can be a more brittle metal and is more prone to micro scratches on the surface. For heirloom pieces, like engagement and wedding rings, we usually recommend 18ct gold. Being worn everyday, 18ct will hold up better over many years than 9ct will, as instead of snapping if it gets bent out of shape, it will simply bend and can be repaired much more easily.
Tied up in durability and appearance is the tarnishing of the gold. Pure gold doesn't corrode or tarnish but the base metals do. The higher the gold content, the less it will tarnish. Both 9ct and 18ct gold should be polished gently with a polishing cloth every now and again, in order to bring back the shine. 9ct Rose Gold is what we find tarnishes the most, due to the high copper content, but again, a quick polish will bring it back to life.
Finally, re-workability is something we as jewellers like to remind our clients of. Even though customers always think of the future and what they will be happy wearing many, many years down the track, sometimes a remodel happens. Style changes, rings are handed down in the family or the unique design you choose at 30 doesn't look right with your style at 50. Due to the higher gold content in 18ct gold, it can much more easily be reworked, melted down or traded in to create new pieces out of.
Overall, if your budget allows for it, we do recommend 18ct gold for it's durability, re-workability and overall finish. But, if your budget only allows for 9ct gold, we are always more than happy to create beautiful pieces in this carat that will last a lifetime if treated well.
If you have any more questions, or need help with choosing your metal, feel free to send us an email.