375 Gold (9 Karat)
Also: 9 Karat, 9ct, 9K, 375/1000
375 Gold refers to a gold alloy with a fineness of 375 parts per thousand (37.5%), known in the Anglo-Saxon world as 9-karat gold and used primarily in the jewellery sector.
375 Gold — also known as 9-karat gold or simply 9ct — contains exactly 0.375 grams of pure gold per gram of alloy. The remainder consists of copper, silver, zinc or other metals that determine the colour, hardness and working properties of the jewellery piece. The melt value calculator can calculate the material value of a 375 piece to the second based on the current gold price.
Fineness and the Karat Scale
The karat scale divides the weight of a gold alloy into 24 equal parts. 9 karat means that 9 of 24 parts are pure gold:
Fineness = (Karat / 24) × 1000
= (9 / 24) × 1000
= 375 ‰
A comparison with other common alloys shows how widely the gold content varies:
| Alloy | Karat | Fineness | Gold Content |
|---|---|---|---|
| 333 Gold | 8 Karat | 333 ‰ | 33.3% |
| 375 Gold | 9 Karat | 375 ‰ | 37.5% |
| 585 Gold | 14 Karat | 585 ‰ | 58.5% |
| 750 Gold | 18 Karat | 750 ‰ | 75.0% |
| 916 Gold | 22 Karat | 916 ‰ | 91.6% |
| Fine Gold | 24 Karat | 999 ‰ | 99.9% |
Alloy Composition and Colours
Since 375 Gold consists of 62.5% base metals, these have a noticeable influence on colour and properties:
- Yellow Gold 375: Copper and silver in balanced proportions; warmer, slightly more reddish tone than 585 yellow gold.
- Red Gold 375: High copper content (often > 50% of the total alloy); strongly reddish colour, particularly robust.
- White Gold 375: Nickel or palladium as brighteners; after processing often rhodium-plated to delay tarnishing.
The high base-metal content makes 375 Gold more susceptible to tarnishing and oxidation than higher-carat alloys, but at the same time increases scratch resistance — an advantage for everyday jewellery.
Prevalence and Hallmarking
9-karat gold is most common in the United Kingdom, Ireland, Russia and parts of the Middle East and India. In Germany, 333 Gold (8 karat) is the traditionally lowest commercial grade; 375 jewellery is imported but appears regularly in the buying trade.
UK Assay Offices stamp 9-karat pieces with the number 375 together with an office mark (anchor for Birmingham, leopard's head for London). In Russia, the stamp 375 is also required by law.
In the EU, gold jewellery must be hallmarked with the metric fineness if marketed as "gold". A missing or illegible stamp is an early warning sign when purchasing scrap gold.
Melt Value and Buying Price
The melt value of a 375 piece follows directly from the current gold spot:
Melt Value (€/g) = Gold Price (€/g) × 0.375
Anyone wishing to sell second-hand jewellery, dental gold or inherited pieces in 9 karat will typically receive 70–90% of the calculated melt value from a buyer — depending on the dealer and piece size. The buying price calculator shows what range is realistic. The calculator is also suitable for dental gold in 9-karat dental alloys.
Tax Notes
375 Gold is not treated as tax-exempt investment gold in Germany within the meaning of § 25c UStG — the fineness must be at least 995 ‰ for that. Jewellery and scrap gold in 9 karat are subject to the margin scheme or full VAT rate on dealer purchases. On a private sale at a profit, the one-year speculative holding period (§ 23 EStG) applies. Note: This is not tax or investment advice — please consult a tax adviser for individual cases.
In Brief
375 Gold (9 karat) is a robust, cost-effective gold alloy with a 37.5% pure-gold content, particularly widespread in the Anglo-Saxon jewellery market. To find out the material value of a piece, use the gold calculator or the melt value calculator.