Density of Gold: 19,320 kg/m³ — Values, Comparisons, and Purity Testing
Gold has a density of 19,320 kg/m³ (19.32 g/cm³), making it one of the most important precious-metal reference values. The number is not only a physical property; it is also a core clue in practical gold authentication.
This page gives exact values, unit conversions, comparisons with other metals, and the method used to test gold purity from density. To calculate mass or volume from this value, use the material density calculator.
Key values
Gold Density: Key Values
kg/m³
19,320 kg/m³
Pure gold at room temperature
g/cm³
19.32 g/cm³
Most common lab reference format
lb/ft³
1,206 lb/ft³
U.S. engineering reference
Values are for 24-karat (99.9%+ pure) gold at approximately 20°C.
Gold melts at 1,064°C; liquid gold density is approximately 17,310 kg/m³.
Metal comparison
Gold Density vs Other Metals
Gold is one of the densest common metals, exceeded only by platinum-group metals and a few rare metals. It is far denser than silver, copper, iron, and aluminum, which is why the same volume of gold feels much heavier than most other metals.
| Metal | Density (kg/m³) | Density (g/cm³) | vs Gold |
|---|---|---|---|
| Osmium | 22,590 | 22.59 | Denser |
| Iridium | 22,560 | 22.56 | Denser |
| Platinum | 21,450 | 21.45 | Denser |
| Gold | 19,320 | 19.32 | — |
| Tungsten | 19,250 | 19.25 | Similar |
| Lead | 11,340 | 11.34 | 41% lighter |
| Silver | 10,490 | 10.49 | 46% lighter |
| Copper | 8,960 | 8.96 | 54% lighter |
| Iron | 7,874 | 7.87 | 59% lighter |
| Aluminum | 2,700 | 2.70 | 86% lighter |
Tungsten has nearly the same density as gold (within 0.4%), which is why tungsten-core fake gold bars exist and why density alone is not always sufficient for authentication.
For broader metal lookup, open the density table. Companion comparison terms include density of lead and density of silver.
Why so dense
Why Is Gold So Dense?
Gold is dense first because each atom is heavy. Gold has atomic number 79 and atomic mass 197 u, making it one of the heaviest stable elements. If you need the general relationship first, start with what is density.
Gold atoms also pack efficiently. Solid gold uses a face-centered cubic (FCC) crystal structure, with a packing efficiency of about 74% and small spacing between neighboring atoms.
Relativistic effects make the 6s electron orbital contract, which pulls the atom into a more compact arrangement. The same physical mechanism helps explain why gold appears yellow instead of silver-white. Aluminum, by contrast, has atomic mass only 27 u and larger spacing, so its density is only 2700 kg/m³.
Alloys
Gold Alloy Densities
Pure 24K gold has the highest density. When other metals are added to create an alloy, the density changes depending on the composition.
Jewelry commonly uses 18K and 14K gold, both of which are less dense than pure gold.
| Gold Purity | Composition | Typical Density |
|---|---|---|
| 24K (999) | 99.9%+ pure gold | 19,320 kg/m³ |
| 22K (916) | 91.6% gold | ~17,700–18,000 kg/m³ |
| 18K (750) | 75% gold | ~15,200–16,400 kg/m³ |
| 14K (585) | 58.5% gold | ~12,900–14,600 kg/m³ |
| 10K (417) | 41.7% gold | ~11,500–12,700 kg/m³ |
Density ranges vary because the alloying metals (silver, copper, palladium, zinc) each have different densities. White gold alloys tend toward the lower end of each range.
Purity testing
Testing Gold Purity with Density
Density is one of the most direct physical ways to test whether a gold item matches its claimed purity. It does not require specialized equipment, only a precision balance and a cup of water.
- Weigh the gold item in air. Record the mass (m_air).
- Fill a container with water and submerge the item fully on a string or thin wire.
- Weigh the item while submerged. Record the submerged mass (m_water).
- Calculate the buoyancy force: Buoyancy = m_air − m_water
- Calculate volume: V = Buoyancy ÷ 1000 (in cm³, using water density ≈ 1 g/cm³)
- Calculate density: ρ = m_air ÷ V
- Compare to the expected density for the stated karat.
Example: A ring weighs 10.0 g in air and 9.45 g submerged.
Buoyancy = 10.0 − 9.45 = 0.55 g → Volume = 0.55 cm³
Density = 10.0 ÷ 0.55 = 18.18 g/cm³
This falls within the 18K gold range (15.2–16.4 g/cm³ is typical, but alloy composition shifts the result — compare against the alloy table above).
Limitation: As noted above, tungsten has nearly the same density as pure gold. A tungsten bar plated with gold will pass a density test. For high-value authentication, density testing should be combined with XRF analysis or ultrasound inspection.
FAQ
Frequently Asked Questions
What is the density of gold in g/cm³?
Pure 24-karat gold has a density of 19.32 g/cm³ at room temperature. This is one of the highest densities among commonly traded metals, exceeded only by platinum-group metals and a few rare elements such as osmium and iridium.
What is the density of gold in kg/m³?
The density of gold is 19,320 kg/m³. To put that in perspective, the same volume of aluminum would weigh only about 2,700 kg — gold is more than seven times denser than aluminum.
Why does gold have such a high density?
Gold atoms are very heavy (atomic mass 197 u) and pack tightly in a face-centered cubic crystal structure. A relativistic effect also causes gold's outer electrons to occupy a smaller orbital radius than expected, pulling atoms closer together and increasing density further.
Can you test if gold is real using density?
Yes. Measure the item's mass in air and again while submerged in water, then calculate density from the buoyancy difference. Pure gold should read close to 19.32 g/cm³, and 18K gold should read roughly 15–16 g/cm³. Note that tungsten has nearly the same density as pure gold, so density testing alone is not conclusive for high-value items.
How does gold alloy karat affect density?
Lower karat gold contains more base metals, which are less dense than gold, so the overall density decreases. 24K gold is ~19.32 g/cm³, 18K is roughly 15.2–16.4 g/cm³, and 14K is roughly 12.9–14.6 g/cm³ depending on the alloying metals used.