WHAT IS THE DIFFERENCE BETWEEN 18K AND 9K GOLD?

Gold facts

Pure gold is a beautiful rich yellow metal worshiped and highly prized by many societies throughout human history. It is well known and accurate to say that pure gold is a soft but highly durable metal not suitable for most jewellery manufacture. Some cultures do prefer pure gold, or near pure gold (22K) jewellery and pay for it either by decreased durability, or financially by making pieces extremely thick and heavy to add strength to designs so they don’t get pushed out of shape through wear!

Pure gold is combined or ‘alloyed’ with other metals to add strength, and hardness . The amount and type of other materials (alloys) added determines the final carat (gold content) of the gold alloy. There are many different recipes for gold alloys, for our purposes we will just describe the more common jewellery alloys.

24K (twenty four carat) gold is pure gold, so all 24 parts are pure gold. Soft and extremely durable.

18K gold is 18 parts pure gold or 75% pure, hence the stamp 750 found inside pieces made from this alloy. This is the main metal used at Metal Urges Fine Jewellery & Diamonds, it is strong, beautiful, durable and does not tarnish, corrode or react with its owners skin. This is an ideal metal alloy for making pieces such as engagement and wedding rings that need to last at least a lifetime!

9K gold is 9 parts pure gold or 37.5% pure, hence the stamp 375 found inside pieces made of this alloy. Due to this metals lower durability and tendency to tarnish, corrode and react with its wearers skin, Metal Urges choose not to work with it. An engagement ring made from 9ct gold can not be expected to last more than a lifetimes normal wear.

The obvious question here is why would an alloy like the 375 above even be labeled as gold. Would it not be more accurate to call it by the name of its other much larger % component alloys? It is after all only just a little over third pure gold.

At the end of the day, 18K gold is worth the higher price. It has twice the gold content of 9K making it superior in terms of durability and performance.

This does not mean that 9K is not a fine choice for certain jewellery. In fact, 9K can be a great choice for dress rings, earrings and pendants that are not worn every day. For pieces such as engagement rings and wedding rings, 18K is a much more durable and long-lasting choice.

It is also important to outline the difference between 18K white gold and platinum when discussing which metals are more suitable for certain designs. Platinum is a white metal that is used almost in its pure form (95%). It is also extremely dense making it heavier than white gold. Platinum is renowned for its hard and long-wearing qualities, which is what makes it so ideal for engagement rings with very fine settings. The other bonus about Platinum is that because it is white in its natural state there is no need to have it rhodium plated as is the case with white gold. What is the catch? Platinum is typically more expensive than 18K gold.