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MyPiece·Hallmarks·999
999
Reference·The stamp

999

Four nines · 99.9% pure

Gold · Silver · Platinum · Palladium

999 means the metal is 99.9% pure — “four nines”, as pure as everyday precious metal gets. On gold it's 24-carat; on silver it's fine silver; it's also the top grade for platinum and palladium. At this purity the metal is soft and rich in colour, which is why 999 is the language of bullion and investment pieces more than of hard-wearing jewellery.

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Hallmark Translator

Translate a purity you know into how any country marks it — gold, silver, platinum, palladium — or compare two countries side by side.

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The reason

Why 99.9%?

999 is the purest grade you'll meet in normal trade — 99.9% pure, with only a whisper of other metal. That purity gives the richest possible colour (deep yellow in gold, bright white in silver and platinum) but also the greatest softness, so 999 pieces scratch and deform easily.

Because of that softness, 999 is the standard of bullion — coins and bars bought for the metal itself — and of cultures that prize pure gold, more than of rings and chains meant for daily wear. For jewellery you'll handle a lot, a harder alloy such as 18K gold or sterling silver usually makes more sense.

Alloy 99.9% pure metal · only a trace of anything else

Around the world

999, metal by metal

The same number means the same purity on every metal — but what it's called, and the mark struck beside it, changes with both the metal and the country.

On gold

24-carat — the purest gold: deep yellow and soft. The standard for bullion and prized across Asia and the Middle East.

Independent assay

United Kingdom

What to look for beside the 999.

Switzerland

What to look for beside the 999.

Israel

What to look for beside the 999.

Mandatory maker's mark

999

China & Hong Kong

What to look for beside the 999.

999

South Korea

Standard

What to look for beside the 999.

Voluntary marking

999

United States

What to look for beside the 999.

Japan

What to look for beside the 999.

Germany

What to look for beside the 999.

999

Brazil

What to look for beside the 999.

On silver

Fine silver — 99.9%, brighter and softer than sterling (925); used for bullion and some modern pieces.

Independent assay

United Kingdom

What to look for beside the 999.

Switzerland

What to look for beside the 999.

Israel

What to look for beside the 999.

Mandatory maker's mark

999

China & Hong Kong

What to look for beside the 999.

Voluntary marking

Japan

What to look for beside the 999.

999

Thailand

What to look for beside the 999.

On platinum

The top platinum grade. Platinum is dense and naturally white, even at this purity.

Independent assay

United Kingdom

What to look for beside the 999.

Switzerland

What to look for beside the 999.

Voluntary marking

Japan

What to look for beside the 999.

999

Germany

What to look for beside the 999.

On palladium

The purest palladium grade — a light, naturally white platinum-group metal.

Independent assay

United Kingdom

What to look for beside the 999.

Switzerland

What to look for beside the 999.

Voluntary marking

999

Germany

What to look for beside the 999.

The catches

What people actually ask

Is 999 the same as 24K?

On gold, yes: 999 means 99.9% pure, which is 24-carat — pure gold. On silver and platinum it means the same purity, but those metals aren't measured in carats, so they're just called fine or 999.

Is 999 gold pure gold?

Essentially — 99.9% pure, the purest grade in normal trade, which is why it's called “four nines”. A slightly finer 999.9 (“four nines fine”) exists for investment bullion.

Why isn't my jewellery stamped 999?

Because pure metal is soft and dents easily. Most jewellery uses a harder alloy — 18K gold, 925 sterling silver — so it survives daily wear. 999 is mainly for bullion and investment pieces.

999 silver vs 925 silver — what's the difference?

999 is fine silver: purer, softer and brighter. 925 is sterling: alloyed with copper for durability, and the standard for everyday jewellery. 999 is closer to bullion; 925 is closer to wearable.

What is 999 metal worth?

It sits closest to the raw spot price by weight, because it's nearly pure — which is exactly why bullion is made to 999. A finished piece can still be worth more for its craftsmanship.

A reference guide, not an authentication service. The same number can appear on different metals, and the mark beside it varies by country, date and maker — consult the relevant assay office or standards body for definitive identification.

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