Gold Karats
Everyone knows what gold is. It’s a shiny, precious, and valuable metal. It goes into jewelry, computers, and sometimes even food and drinks. But, not all gold is created equal. You’ve probably heard of 10k, 14k, and maybe 24k gold, but what does it all mean? The ‘k’ stands for karat and a karat is a measure of purity. This is not to be confused with ‘carat’ which is the unit used to weigh diamonds and other precious stones. Each karat represents 1/24th of purity of a piece of gold. For example, 10 karat gold is 10/24ths pure, so a little less than half of it is pure gold, 14 karat is 14/24ths pure so more than half of it is pure gold. And lastly, 24 karat gold is 100% pure gold with no other metals mixed in.
What does all this have to do with jewelry? Gold in its purest form has a very rich yellow color and can easily be polished to a perfect mirror finish. As far as value goes, if purchased directly from a bullion site, you will be charged a minimal markup and a shipping charge so you’ll hardly lose anything if you can find the right buyer. These all sound like great reasons to make jewelry out of the stuff but you’ll have a very hard time finding 24k gold jewelry anywhere. Naturally, there are a few factors preventing this practice. Gold in its purest form is incredibly malleable, heavy, and expensive. Pure 24k gold can be dented with just your fingernail and a fair amount of effort. One cup of water weighs half a pound while a cup of gold would weigh about 10 pounds. As of January 2020, that cup of gold would be worth around $225,000. As a result of these factors, most 24k gold is kept in the form of bullion bars. One way to wear 24k gold bullion is to place it into a bezel similar to the one pictured below.
On the other end of the spectrum of gold purity is 10k gold. 10k gold is only 10/24ths or 41.7% pure gold. What makes up the other 58.3% of that gold? The remaining parts are usually a mixture of silver, nickel, palladium, and several other metals. This mixture does vary from manufacturer to manufacturer so don’t be alarmed if a jeweler mentions a metal not in that list. All these metals alloyed with the gold affect it in significant ways. Those metals are all naturally gray in color which makes the color shift from the harsh, almost orange, reddish-yellow of pure gold to the paler, soft yellow everyone is more familiar with. These other metals are also much harder and less dense than pure gold giving the finished piece much more durability and more manageable weight. And finally, with the exception of palladium, these other metals are cheaper than pure gold making 10k gold jewelry a good deal more accessible to the average consumer.
Gold Karat | Gold Content | Non-gold Content |
10k | 41.7% | 58.3% |
14k | 58.3% | 41.7% |
18k | 75% | 25% |
21k | 87.5% | 12.5% |
22k | 91.7% | 8.3% |
24k | 100% | 0% |
As an industry standard, 10k gold is the minimum purity used in jewelry. Any lower than that and the non-gold metals will be prone to tarnishing and diminishing the appearance of the jewelry. Generally, jewelry that sees less frequent wear or holds more personal significance will use a higher karat gold in its construction. For example, most simple chains and pendants will use 10k gold as they’re appropriate for everyday wear and experience a lot of movement throughout the day. Taking a step up, engagement rings are usually made using 14k or even 18k gold. 18k gold sees a lot of use in luxury watches such as those made by Rolex, Audemars Piguet, and many others. In some regions, 22k gold jewelry is owned by families but only ever brought out and worn during crucial life events and celebrations.