Gold testing methods / How to check gold purity
Here are some ways to test the purity of gold at home for Indian users:
1. Magnet Test
- What to Do: Hold a magnet near the gold item.
- What to Check: Pure gold is non-magnetic, so if the item is attracted to the magnet, it likely contains other metals.
- Caution: This test only checks for magnetic metals like iron or nickel. Non-magnetic metals, like copper, won’t show a reaction either.
2. Float Test
- What to Do: Drop the gold item into a glass of water.
- What to Check: Pure gold is dense and will sink to the bottom. If it floats or hovers, it’s likely fake or mixed with lighter metals.
- Caution: This test isn’t definitive for distinguishing between pure and impure gold but can identify heavily adulterated gold.
3. Ceramic Scratch Test
- What to Do: Rub the gold item across an unglazed ceramic plate.
- What to Check: If it leaves a gold streak, it’s likely real gold. If it leaves a black mark, the gold may be fake or of low purity.
- Caution: Be gentle to avoid damaging your gold item.
4. Vinegar Test
- What to Do: Place a few drops of vinegar on the gold item or soak it in vinegar for a few minutes.
- What to Check: Pure gold won’t react to vinegar. If the metal changes color or tarnishes, it’s not pure gold.
- Caution: Use this test cautiously to avoid damaging other metals in the item.
5. Nitric Acid Test
- What to Do: Apply a small drop of nitric acid to the gold item.
- What to Check: Real gold won’t react to nitric acid. Fake or impure gold may turn green or black, indicating a reaction.
- Caution: Nitric acid is a strong chemical; use protective gear and perform this test outdoors or in a well-ventilated area.
6. BIS Hallmark Check
- What to Do: Check for the Bureau of Indian Standards (BIS) hallmark on the gold item, usually in a tiny, stamped symbol.
- What to Check: The hallmark certifies that the gold meets purity standards in India. Look for the BIS logo, purity in karats (e.g., 22K), and year of hallmarking.
- Caution: Be familiar with what the BIS hallmark looks like to ensure it’s authentic.
7. Gold Density Test
- What to Do: Weigh your gold item on a scale and then measure its volume by submerging it in water.
- What to Check: Pure gold has a density of around 19.3 g/cm³. You can calculate density by dividing the mass by the volume (water displacement).
- Caution: This test requires accurate measurement equipment to get precise results.
These methods can give a reasonable indication of gold purity at home, but for highly accurate results, a professional jeweler or testing center would be more reliable.
