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MyPiece·Hallmarks·990
990
Reference·The stamp

990

Chuk Kam (990) · 99% pure

Gold · Silver · Platinum · Palladium

990 means 99% pure — “Chuk Kam” (足金) in the Chinese gold trade, near-pure fine gold just below the four-nines of 999. China's national standard also recognises 990 for silver, platinum and palladium. At 99% the metal is soft and richly coloured, the language of high-purity gold culture across China and Hong Kong.

Tool

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%?

Chuk Kam (足金, “full gold”) is the cultural standard of Chinese gold — near-pure gold valued as wealth, traditionally 990 and above (the market now often runs to 999). It's soft, deep-yellow and bought largely by weight.

China's national standard (GB 11887) also lists 990 grades for silver, platinum and palladium, though gold is where you'll meet the figure most often.

Around the world

990, 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

Chuk Kam (足金) — 99% fine gold, the near-pure standard of the Chinese and Hong Kong trade; deep yellow and soft.

Mandatory maker's mark

990

China & Hong Kong

Standard

Known as Chuk kam. What to look for beside the 990.

On silver

99% silver — a high fine-silver grade in China's national standard (GB 11887).

Independent assay

India

What to look for beside the 990.

Israel

What to look for beside the 990.

Mandatory maker's mark

990

China & Hong Kong

What to look for beside the 990.

On platinum

99% platinum — a high grade recognised in China's national standard.

Mandatory maker's mark

990

China & Hong Kong

What to look for beside the 990.

On palladium

99% palladium — a high grade recognised in China's national standard.

Mandatory maker's mark

990

China & Hong Kong

What to look for beside the 990.

The catches

What people actually ask

What is Chuk Kam / 足金?

It's near-pure fine gold — 99% — the high-purity standard of the Chinese and Hong Kong gold trade.

Is 990 gold pure?

Almost — 99% pure, just below the four-nines of 999. Rich-coloured and soft.

990 vs 999 — what's the difference?

Both are near-pure. 999 (“four nines”) is slightly purer; 990 is the traditional Chuk Kam threshold, though the market now often runs to 999.

Why is Chinese gold so pure?

Because gold is valued there as a store of wealth as much as adornment, so near-pure, soft, high-carat gold is preferred.

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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