What is 18k gold?

Buying gold jewelry can be a little overwhelming, especially if you’re just starting to build your fine jewelry collection. Gold comes in different karats or purity not to be mistaken with carat, the unit used to measure stone size.

In jewelry, the range of purity is from 10k to 24k and each kind has differences in color, durability and value.

Karat = Purity of Gold
Pure gold is 24k. That means 24/24 parts are gold. In the case of 18k gold jewelry then, 18 of 24 parts are gold and the remaining 6 parts are other alloys mixed in (most commonly zinc, copper, silver and nickel). The higher the karat, the less other alloys have been combined with gold.

Gold jewelry is usually marked with numbers that indicate the level of purity so you know what you are buying. For example, 18k gold jewelry is stamped with 750. That number indicates that the metal is 75% gold (18/24 = 0.75).

10K (10/24) = 41.7% / 416/417
14K (14/24) = 58.3% / 583/585
18K (18/24)= 75% / 750
22K (22/24) = 91.7% / 916/917
24K (24/24) = 99.9% / 999

Metal Color
Color is determined by the mix of alloys. When there is more gold in the metal, the more vibrant it will appear. So for example, 10k gold would be significantly lighter than 21k gold. 18k rose gold jewelry would have 18 parts gold, and in its remaining 6 parts would have more copper than the other white metals to make the hue more pinkish. 

Value
The purer the metal, the more expensive or higher the value but purer does not mean better! Pure gold, or 24k gold, is a very soft metal. It has a bright orangey hue and is not ideal for jewelry designs that include stones, as the metal is easily bendable and stones can fall out. 18k gold jewelry, on the other hand, has a mix of alloys that increase its durability. It is less prone to being scratched or bent out of shape. Therefore, it is usually the preferred metal for engagement rings or wedding rings and diamond jewelry in general.

At Sheen Jewelry, we use 18k gold for all of our jewelry. That includes 18k rose gold and 18k white gold as well.