See why gold's chemical symbol is Au, what aurum means, and how atomic number 79 connects to jewelry, bullion, purity marks, and basic chemistry.
- Au identifies the element; karat and fineness marks describe purity.
- The symbol comes from Latin aurum, not the English word gold.
- Use atomic number 79 to connect the symbol to the periodic table.
Quick answer: Gold’s chemical symbol is Au, from the Latin aurum; its atomic number is 79. In financial listings, codes such as XAU, XAU/USD, XAUUSD, and GC identify market data or specific products, not the chemical symbol.
Gold labels answer different questions: a chemical symbol names the element, a purity mark describes the gold content of an item, and a market code identifies a quote or contract.
TL;DR: What Is the Symbol for Gold?
- Au is the chemical symbol for the element gold.
- The letters come from aurum, the Latin word for gold.
- 79 is gold’s atomic number: each gold atom has 79 protons.
- Marks such as 14K, 585, 750, and 999 describe purity or fineness, not the element symbol.
- XAU, XAUUSD, and GC are market or contract codes; their meanings depend on the instrument.
Gold Symbol Facts at a Glance
| Fact | Correct value | What it means |
|---|---|---|
| Chemical symbol | Au | The standard abbreviation for the element gold. |
| Name source | Latin aurum | The reason the symbol is Au instead of G or Go. |
| Atomic number | 79 | The number of protons in every gold atom. |
| Periodic-table position | Period 6, Group 11 | Gold sits with copper and silver in the group often called the coinage metals. |
| Purity marks | 24K, 18K, 14K, 999, 750, 585 | These describe the gold content of an alloy or bullion item. |
For element data, the NIH PubChem element record lists gold as Au with atomic number 79. The NIST atomic data table for gold also identifies Au and atomic number 79.
Why Is Gold’s Symbol Au Instead of G?
Gold’s symbol preserves its Latin name, aurum. Some other chemical symbols also preserve Latin names that differ from the English element name: silver is Ag from argentum, iron is Fe from ferrum, and lead is Pb from plumbum.
In chemistry, assay records, and technical descriptions, Au names the element regardless of the surrounding language. It does not by itself describe a piece of jewelry’s purity or a financial product.
A historical symbol for gold
Alchemy also associated gold with a solar symbol, distinct from the modern chemical symbol Au. The Royal Society of Chemistry’s gold entry notes that the traditional alchemical sign it shows is also used as a Sun symbol. The Unicode alchemical-symbol chart names U+1F71A as an alchemical symbol for gold and points to ☉, the Sun sign. Historical forms vary; neither is gold’s modern chemical symbol.
What Atomic Number 79 Tells You
Atomic number 79 means that each gold atom has 79 protons in its nucleus. It is not a purity grade, a percentage of gold in an object, or a trading code.
The Royal Society of Chemistry’s periodic-table entry places gold in Group 11 and Period 6 and identifies it as a solid element at room temperature.
Au vs. Karat: Element Symbol vs. Purity
Au identifies the element. Karat and fineness describe how much gold an alloy or bullion item contains.
The World Gold Council’s jewelry guide explains that caratage measures gold purity and fineness expresses purity in parts per thousand.
| Mark | What it describes | Common meaning |
|---|---|---|
| Au | Chemical symbol | The element gold; it does not state purity. |
| 24K | Karat purity | Nearly pure gold, subject to the applicable product standard. |
| 18K / 750 | Alloy purity | About 75% gold by mass. |
| 14K / 585 | Alloy purity | About 58.5% gold by mass. |
| 999 / 999.9 | Bullion fineness | High-purity gold expressed in parts per thousand. |
Real jewelry may use karat, fineness, maker, or hallmark stamps instead of Au. For more detail, see our guides to 14K gold, 18K gold, and how to tell if rose gold is real.
Gold Market Symbols: XAU, XAUUSD, and GC
Trading screens and exchange listings use codes for gold quotes or products. These codes are different from Au, the chemical symbol.
| Code | Where it is used | What it identifies |
|---|---|---|
| Au | Chemistry and element data | The element gold. |
| XAU | ISO 4217 metal code | A precious-metal code. The Oesterreichische Nationalbank’s ISO-code directory lists XAU for gold and gives ounce as the unit. |
| XAU/USD or XAUUSD | Some trading-platform listings | A gold instrument quoted against the U.S. dollar. For example, IG lists XAUUSD in its MT4 product specifications; product terms depend on the provider. |
| GC | CME Group Gold Futures | The product code for standard gold futures; CME Group lists a 100-troy-ounce contract. |
Platform labels and contract terms are not universal. Check the product’s contract size, unit, expiry, and settlement details before comparing it with physical gold.
If you mean a physical bar or coin, the code does not replace its purity and product details. Continue with our guides to gold and silver bullion, gold bars, gold coins, or testing gold coins.
Editorial Perspective
Before relying on a gold label, ask what it identifies: the element, an item’s purity, or a traded product. For physical gold, check the item’s marks and supporting test or assay documentation; for a market product, read the provider’s contract specifications.
Common Gold-Symbol Mix-Ups
Thinking Au means pure or verified gold
Au names the element. It does not establish an item’s fineness or authenticity on its own.
Reading 79 as a percentage or price code
Gold’s atomic number counts protons. It does not mean an item is 79% gold and is not a market ticker.
Treating market codes as chemical symbols
XAU, XAUUSD, and GC belong to different market or contract contexts. Check the specific product listing rather than assuming the codes are interchangeable.
Three labels answer three questions
Au names the element, 14K or 750 describes purity, and a code such as XAUUSD identifies a market instrument. None of these labels alone proves that a specific item is authentic or suitable for a particular purpose.
Bottom Line
Gold’s chemical symbol is Au, from aurum; its atomic number is 79. Karat and fineness marks describe purity, while XAU, XAUUSD, and GC refer to market codes or products whose terms depend on the applicable standard or provider.
FAQ: What Is the Symbol for Gold?
What is the chemical symbol for gold?
The chemical symbol for gold is Au.
Why is gold’s symbol Au?
Au comes from aurum, the Latin word for gold, rather than from the English word.
What is gold’s atomic number?
Gold’s atomic number is 79. Every gold atom has 79 protons in its nucleus.
Does Au mean 24K gold?
No. Au identifies the element; 24K describes a gold-purity level.
What is the trading symbol for gold?
There is no single code for every gold product. XAU is a metal code, some platforms use XAUUSD for a gold-versus-dollar instrument, and CME Group uses GC for its standard gold futures; check the relevant product specifications.
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