Choose a gold-testing method based on what you actually need to know: a quick red-flag screen, approximate karat, physical density, elemental composition or a high-confidence professional result.
Match the method to your purpose.
| Method | Main Use | Destructive? | Main Limitation |
|---|---|---|---|
| Magnet | Quick screening | No | Many non-gold metals are also non-magnetic |
| Touchstone / Acid | Karat comparison | Relatively low | Requires sampling and corrosive chemicals |
| Density / SG | Physical screening | No | Hollow and mixed-material items complicate results |
| XRF | Elemental composition | Generally no | Calibration, surface and geometry matter |
| Professional Assay | High-confidence composition | Method dependent | Cost, access and sometimes sampling |
Different methods measure different properties. A magnet responds to magnetic behavior. Density measures mass-to-volume behavior. Touchstone testing compares chemical resistance. XRF analyzes elemental composition. Because each sees something different, combining independent evidence is often stronger than relying on one simple test.
For a high-value purchase, move beyond visual clues and inexpensive screening tests. A professional XRF measurement or suitable laboratory analysis can provide much stronger evidence than appearance or a magnet alone.
There is no single best method for every purpose.
They solve different problems; XRF provides much richer composition information.
No.
Touchstone testing is relatively nondestructive but normally involves sampling and corrosive chemicals.
Use independent evidence and consider professional analytical testing.