What karat counts
Karat is the proportion of pure gold in an alloy, measured in 24ths. Pure gold is 24K. An 18K piece is 18 parts gold and 6 parts other metals, which works out to 75 percent gold. Fourteen karat is 58.3 percent, and 10K is 41.7 percent.
The remaining metal is not filler. Copper, silver, zinc, palladium, and nickel are added to change color and to make the alloy harder than pure gold, which is soft enough to dent with a fingernail.
In the US, pieces sold as gold must be stamped with the karat and the maker's mark. A stamp reading 14K or 585 refers to the same alloy.
Karat also sets melt value. A jeweler buying scrap pays by gold content, so an 18K band is worth more per gram than a 14K band of identical weight, whatever the design or the maker. That matters if a piece is ever sold for its metal rather than as jewelry.
10K gold: the hardest of the three
Ten karat holds the least gold and the most alloy, which makes it the hardest and most scratch-resistant of the common karats. It suits thin bands, small earrings, and pieces worn by people who work with their hands.
The trade-off is color. At 41.7 percent gold, yellow 10K reads paler than 14K, and rose 10K reads more copper than pink. On a wide band the difference is easy to see next to a higher karat piece.
14K gold: the middle default
Fourteen karat is the standard for US bridal jewelry for good reason. It holds a deep enough color, resists denting, and takes prongs and fine detail without deforming.
It is also the karat most people can wear daily for years without visible wear on the shank. A 14K solitaire at 2mm will outlast a 10K band of the same width in most cases, because the alloy balance favors toughness over pure hardness.
18K gold: color and weight
Eighteen karat is 75 percent gold. Yellow 18K has the warm, saturated tone that most people picture when they think of gold, and it holds that color through polishing without plating.
It is softer than 14K. A 1.5mm 18K band will show dents and scratches sooner than the same band in 14K, and thin prongs in 18K need more frequent checking. For a wide band or a bezel setting, the softness is not a problem. For a thin shank with tall prongs, it is.
| Karat | Gold content | Hardness | Color depth | Best for |
|---|---|---|---|---|
| 10K | 41.7% | Highest | Palest | Thin bands, everyday earrings, active wear |
| 14K | 58.3% | Good | Medium | Engagement rings, wedding bands, chains |
| 18K | 75.0% | Softest | Deepest | Wide bands, bezels, pendants, dress pieces |
| PT950 | 95% platinum | Dense, work-hardens | White only | Heavy daily rings, heirloom builds |
Color comes from the alloy, not the karat
Yellow gold is gold with copper and silver. White gold is gold with palladium, nickel, or silver, and it is rhodium plated to reach a bright white surface. Rose gold gets its tone from a higher copper share.
White gold is not naturally white. The rhodium layer on top is what you see, and that layer wears with friction over one to three years of daily wear. Re-plating restores it and costs far less than a new setting.
Rose gold at 18K is pinker and softer than at 14K. If the color needs to match an existing piece, match the karat as well as the tone.
Price and how it scales
Metal cost tracks gold content, so 18K costs roughly a third more in metal than 14K at the same weight, and 14K costs about 40 percent more than 10K. Setting labor does not change with karat, which means the percentage gap between finished prices is smaller than the gap in raw metal.
On a custom piece the difference between 14K and 18K is often a few hundred dollars, not a few thousand. That is worth knowing before trading down a karat to protect a budget that would absorb the change.
Matching karat to the piece
- Engagement and wedding rings worn daily: 14K for the balance of color and toughness, 18K if the band is 2mm or wider.
- Chains and bracelets: 14K, since links take abrasion against skin and clothing.
- Studs and small hoops: 14K or 10K, where metal weight is low and durability matters more than color depth.
- Pendants and dress pieces: 18K, where the surface is protected and the color is the point.
Mixing karats in one stack is fine as long as the colors match. A 10K band next to an 18K band in the same color family will read slightly different in tone, and the difference shows under daylight more than indoors.
All three karats work with moissanite, lab-grown diamond, and the lab-grown colored stones we set. If you are still deciding on the design, the custom design service will quote the same setting in each karat so you can compare. The learn section covers plating and finishing, and the FAQ explains the lifetime manufacturing warranty that applies to the metal work.