Understanding Gold Purity: Karats vs. Fineness
Understanding gold purity is essential for anyone involved in gold trading, processing, or investment. This guide explains the two main systems for measuring gold purity: karats and fineness.
The Karat System
The karat system divides gold purity into 24 parts. Pure gold is 24 karats, meaning it's 100% gold. Here's how the karat system works:
- 24K Gold: 100% pure gold (24/24 parts)
- 22K Gold: 91.7% gold (22/24 parts)
- 18K Gold: 75% gold (18/24 parts)
- 14K Gold: 58.3% gold (14/24 parts)
- 10K Gold: 41.7% gold (10/24 parts)
The Fineness System
The fineness system measures gold purity in parts per thousand. Pure gold is 999.9 fineness, which is commonly referred to as "four nines" fine.
- 999.9: 99.99% pure gold
- 995: 99.5% pure gold
- 916: 91.6% pure gold (equivalent to 22K)
- 750: 75% pure gold (equivalent to 18K)
- 585: 58.5% pure gold (equivalent to 14K)
Practical Applications
In professional gold refining, we typically work with fineness measurements as they provide more precise control over purity levels. Most investment-grade gold is 999.9 fineness, while jewelry often uses lower purities for durability.
Professional Tip
When assessing gold purity, always use professional assaying equipment. Visual inspection and acid tests can give preliminary results, but only laboratory analysis provides accurate purity measurements.
Conversion Guide
Here's a quick reference for converting between karats and fineness:
| Karat | Fineness | Gold Percentage |
|---|---|---|
| 24K | 999.9 | 99.99% |
| 22K | 916 | 91.6% |
| 18K | 750 | 75% |
| 14K | 585 | 58.5% |
Understanding these measurement systems is crucial for making informed decisions in gold trading and processing. At MetGold, we ensure all our refined gold meets the highest purity standards of 999.9 fineness.
About the Author
This article was written by our Chief Metallurgist, Jumanne Mdongo, who has over 15 years of experience in gold processing and refining technologies.