A karat mark tells you how much of a gold alloy is pure gold. It is one of the first clues in an evaluation, but it is not the only thing a professional buyer considers.
Understanding the numbers
Pure gold is described as 24 karat. Because pure gold is very soft, jewelry is commonly mixed with other metals to improve strength, color and wearability.
- 10K gold is approximately 41.7% pure gold
- 14K gold is approximately 58.5% pure gold
- 18K gold is 75% pure gold
- 22K gold is approximately 91.7% pure gold
Common hallmarks
A piece may be marked 10K, 14K, 18K or with a number such as 417, 585 or 750. Those numerical marks represent the approximate parts of pure gold per thousand.
Hallmarks can be worn, tiny or misleading. Some pieces have been repaired with different metals, and some stamped items may not test as expected. That is why professional testing remains important.
Why equal weights can have different values
A 14K item and an 18K item of the same weight contain different amounts of pure gold. Stones, non-gold components and hollow construction can also affect how a piece is evaluated.
The full evaluation brings together purity, precious-metal weight, market conditions and any additional collectible or resale value.
Every item is different. The most reliable way to understand what you have is through an in-person evaluation.