A 375 mark generally means the gold alloy is 375 parts gold per 1,000, or 37.5% gold, which corresponds to 9K. A 585 mark generally means 585 parts gold per 1,000, or 58.5% gold, which corresponds to 14K. These numbers describe fineness: the proportion of pure gold in the alloy. They do not, by themselves, tell you the color, weight, construction, maker, condition, or whether a piece has been independently tested.
This guide explains how karat and millesimal fineness marks relate, what other marks to look for, and what to verify before buying.
375 and 585 gold at a glance
| Mark | Gold content | Karat equivalent | Other metal content |
|---|---|---|---|
| 375 | 375 parts per 1,000, or 37.5% | 9K | 62.5% |
| 585 | 585 parts per 1,000, or 58.5% | 14K | 41.5% |
| 750 | 750 parts per 1,000, or 75% | 18K | 25% |
| 916 or 917 | About 91.6% or 91.7% | 22K | About 8.3% or 8.4% |
| 999 | About 99.9% | Approximately 24K | Trace amount |
The exact marks used and the legal requirements surrounding them vary by market. A number stamped on a piece should therefore be read together with the seller's description, the maker or sponsor mark, and any applicable assay or hallmark information.
What does 375 mean on gold jewelry?
The number 375 is a millesimal fineness mark. It expresses gold content in parts per thousand: 375 out of 1,000 parts of the alloy are gold. That equals 37.5% gold.
In karat terms, 9 parts out of 24 are gold:
9 / 24 = 0.375 = 37.5% = 375 parts per thousand
That is why 375 and 9K describe the same nominal gold proportion. The remaining 62.5% consists of other metals used in the alloy. A fineness number does not identify those metals, so it should not be used to infer color or suitability for a particular wearer.
What does 585 mean on gold jewelry?
The number 585 means the alloy contains 585 parts gold per 1,000, or 58.5% gold. The karat calculation is:
14 / 24 = 0.5833...
The practical fineness standard is commonly expressed as 585, so 585 and 14K are used to identify the same nominal gold category. The remaining 41.5% consists of other metals in the alloy.
If you are deciding between the two categories, our 9K vs 14K gold comparison explains the differences in gold content, color, price, and everyday decision-making.
Karat and carat: are they the same?
In U.S. jewelry descriptions, karat, abbreviated K or Kt, refers to gold purity. In some other markets, carat, abbreviated ct, is also used for gold fineness. Context matters because carat is also a unit of gemstone weight.
Examples that may indicate gold purity include:
- 9K, 9Kt, or 9ct
- 14K, 14Kt, or 14ct
- 375 or 585
A seller should describe the material clearly enough that a shopper does not need to guess whether a number refers to gold content, gemstone weight, a model number, or something else.
Does a 375 or 585 stamp prove that jewelry is genuine?
No stamp should be treated as the only proof of material. Marks can be incomplete, worn, incorrectly applied, or counterfeited. Some genuine small or older pieces may also have markings that are difficult to read or follow a different system.
For a U.S. purchase, the Federal Trade Commission advises shoppers to look for a karat quality mark and, near it, the name or U.S. registered trademark of the company that stands behind the mark.
In the UK, a complete legal hallmark is a group of marks rather than only a fineness number. UK government hallmarking guidance explains that the compulsory components include a sponsor or maker mark, a metal and fineness mark, and an Assay Office mark for items subject to hallmarking requirements.
What other marks might appear beside the purity mark?
Depending on the country, maker, age, and construction of the jewelry, you may see:
- Maker, sponsor, or responsibility mark: identifies the business or person standing behind the mark.
- Assay Office mark: identifies the office that tested and hallmarked an item in a formal hallmarking system.
- Date letter: may indicate a hallmarking year in systems where date letters are used.
- Color or product code: may be an internal manufacturer code and not a purity statement.
- Plating qualifier: terms such as plated, electroplate, overlay, RGP, or vermeil change the meaning of a nearby gold reference.
Never isolate one number from the rest of the marks. For example, a gold fineness reference attached to a plating description does not mean the whole piece is made from that gold alloy. Our guide to solid gold, gold plated, and vermeil explains these constructions.
Can you tell yellow, white, or rose gold from 375 or 585?
No. The fineness number describes how much gold is in the alloy, not its color. Yellow, white, and rose appearances depend on the full alloy recipe and any surface treatment or finish.
Two pieces marked 585 can look different because their remaining alloy metals, polish, surface treatment, lighting, and age may differ. Likewise, 375 does not automatically mean yellow gold, and 585 does not automatically mean white or rose gold.
Does a higher number mean the jewelry is better?
A higher fineness number means a higher proportion of pure gold. It does not automatically mean that a design is better made, more comfortable, more durable in every situation, or better suited to a particular buyer.
Construction also matters. Check the thickness of delicate parts, closure design, post length, stone setting, finish, repairability, and how the piece fits your routine. Gold content is one useful specification, not a complete quality score.
How to check a gold listing before buying
- Read the full material description. Look for the karat or fineness and whether the piece is an alloy throughout, hollow, filled, or plated.
- Check the selected variant. Do not assume every option on a product page has the same karat, color, stone, price, or availability.
- Look for the business behind the mark. A maker, sponsor, or responsibility mark adds context to the purity mark.
- Check all components. Posts, backings, clasps, chains, and decorative parts may need separate material descriptions.
- Keep the listing and receipt. Save the exact description and selected variant as a record of what was represented.
- Ask for professional testing when necessary. For a pre-owned, unverified, or high-value piece, an independent qualified professional can assess the specific item.
Shopping by style without assuming karat
When browsing KuGOLD, confirm the available material on the selected product and variant rather than assuming every design is offered in every karat. You can explore the verified public Studs collection or Pendants collection, then review the exact options shown on each product page.
Frequently asked questions
Is 375 real gold?
375 is a fineness designation for an alloy containing 37.5% gold, equivalent to 9K. Whether a specific item matches its stamp requires reliable provenance or appropriate testing.
Is 585 the same as 14K?
Yes, 585 is the commonly used millesimal fineness designation corresponding to 14K gold. It represents 58.5% gold in the alloy.
Is 585 better than 375?
585 contains a higher proportion of gold than 375. Which one is preferable depends on budget, desired color, design, construction, and how the jewelry will be worn.
What does 925 mean?
925 is commonly associated with sterling silver, not gold. If it appears with a gold-colored piece, read every nearby qualifier because the item may be gold plated over sterling silver rather than made from a gold alloy throughout.
What if the stamp is missing or unreadable?
Do not identify metal from color alone. Review the seller's documentation and, when the answer materially affects value or use, ask an independent qualified professional to test the piece.
The short version: 375 and 585 are useful purity signals, but responsible buying requires the complete description, the selected variant, the party standing behind the mark, and the construction of the whole piece.