- Jewelry Identifier
- Gold alloys
- 9K Yellow Gold
* 9K gold
9K Yellow Gold: what it's made of, its purity, and its value
UK / Commonwealth minimum 'gold'. Brassier yellow than higher karats. Below US gold-legality threshold.
Published May 30, 2026
Quick facts
- Karat
- 9K
- Purity
- 37.5%
- Fineness
- 375/1000
- Color
- Yellow
- Density
- 11.1 g/cm³
- Melting point
- 880 °C
What it's made of
- Gold
- 37.5%
- Silver
- 18%
- Copper
- 37%
- Zinc
- 7.5%
The gold content is fixed at 37.5% — that's what makes it 9K. The remaining metals are what set the color: Silver and copper are added mainly for hardness; they leave the warm yellow of the gold largely intact.
About 9K Yellow Gold
UK / Commonwealth minimum 'gold'. Brassier yellow than higher karats. Below US gold-legality threshold.
How much it's worth
The melt value of a 9K Yellow Gold piece is gold spot price × 0.375 × weight (g), because only 37.5% of the metal is gold. A buyer then deducts roughly 5–15% for refining and margin, so a cash offer lands just under that figure. Higher-karat gold packs in more gold per gram, so it carries a higher melt value — but it's also softer and scratches more easily, which is why everyday jewelry often uses lower karats.
* Frequently asked
FAQ
- Q. How much gold is in 9K Yellow Gold?
- A. 37.5% by weight. 9K means 9 parts gold out of 24, which works out to 375/1000 fineness — the rest is alloy metals added for color and durability.
- Q. Is 9K Yellow Gold real gold?
- A. Yes. 9K is genuine gold — it's 37.5% pure gold by weight, alloyed with other metals. It is not gold-plated or gold-filled; the gold runs all the way through.
- Q. Why is 9K Yellow Gold yellow?
- A. The color comes from the metals mixed with the gold. Silver and copper are added mainly for hardness; they leave the warm yellow of the gold largely intact.
- Q. Will 9K Yellow Gold tarnish or cause skin reactions?
- A. Solid 9K gold doesn't tarnish, and this alloy is nickel-free, so skin reactions are rare. Surface films usually come from skin oils or lotions and wipe off with a soft cloth.
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