Authenticity Test
Gold Density / Authenticity Calculator
Test if your gold is genuine using the Archimedes water displacement method. Pure 24K gold has a density of 19.3 g/cm³.
Pure gold density = 19.3 g/cm³. To test, measure your item's weight in air and its weight submerged in water (water displacement method / Archimedes test).
- Volume (cm³)
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- Measured Density
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- Expected (24K)
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- Verdict
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| Karat | Purity | Density (g/cm³) |
|---|---|---|
| 24K | 99.9% | 19.32 |
| 22K | 91.7% | 17.7–18.0 |
| 21K | 87.5% | 16.7–17.5 |
| 18K | 75.0% | 15.2–15.9 |
| 14K | 58.5% | 12.9–14.6 |
| Platinum | 95% | 21.4 |
| Tungsten | — | 19.25 (fake gold risk) |
Frequently Asked Questions
What is the density of pure gold?+
Pure 24K gold has a density of 19.32 g/cm³ (grams per cubic centimeter). It's one of the densest common metals, much denser than lead (11.3), silver (10.5), or copper (8.9).
How do I measure density at home?+
Use the water displacement method: weigh the gold in air, then weigh it while suspended in water on a string (not touching sides/bottom). Density = weight-in-air ÷ (weight-in-air − weight-in-water).
What density indicates fake gold?+
Density below 15 g/cm³ strongly suggests the item is not primarily gold. Between 15–17 g/cm³ could be 14K–18K or a heavy alloy. Very close to 19.3 is consistent with 22K–24K gold.
Why can't density alone confirm gold authenticity?+
Tungsten has a density of 19.25 g/cm³ — almost identical to gold. A tungsten bar gold-plated on the outside will pass a density test. XRF or acid tests are needed for bars.
What is the density of 18K gold?+
18K gold (75% gold + 25% alloy) has a density of approximately 15.5–16.0 g/cm³ depending on the alloy metals used (silver lowers it; copper raises it slightly).