It can still be a low-purity solid gold alloy that contains magnetic metals. On the other hand, a piece may be gold plated, but it will not attach to a magnet because its core metal is non-magnetic.
Acid test.
An acid test can reveal the karat of solid gold jewelry, but it can also show whether jewelry is solid gold or gold-plated. With an acid test, a small sample of the jewelry is removed and exposed to acid to induce a color change. The resulting colors indicate which type of metal the jewelry is made of.
Fill a cup or bowl with water and carefully drop your gold piece into it. If the gold is real, it will sink to the bottom of the cup. If it's fake, it will float to the top or hover in the middle of the cup.
Gold plating can be added to almost any metal, including brass, copper or nickel. Silver items can also be gold-plated. Some pieces will actually be plated with a wide range of metals even if you can only see the gold plating.
Tarnishing: The main con with gold plating, rather than using real gold, is tarnishing. Tarnishing is likely to occur over a long period of time due to wear and tear, causing the metal underneath the gold plating beginning to show through.
Apply acid to the metal.
Apply concentrated acid to the metal. Brass will react with acids and gold will not. If you see bubbling or discoloration where the acid is applied, your piece is brass. If there is no change after applying the acid, you have gold.
If your gold piece turns black or green when the vinegar is on it, or if it starts to smoke or fizzle at all when the vinegar touches it, it is most likely not real gold. If your gold piece does not change colors and does not fizzle or react to the vinegar in any way, it is probably real.
Pure gold on its own cannot stick to a magnet. However, if you have an alloy of gold, then it could stick to a magnet. An example of a gold alloy that may stick to a magnet is gold with over 20% of its atoms replaced by iron. In very cold temperatures this alloy of gold may magnetize all on its own.
No, gold-plated does not mean fake. Gold-plated jewelry uses the same gold for its golden layer as solid gold jewelry. The only difference is that solid gold is made entirely of gold and alloys, while gold-plated jewelry has a metal base that is covered in gold.
No, gold-plated does not necessarily mean fake. Gold-plated jewelry and other items are made of a base metal, such as copper or brass, that is coated with a layer of gold through a process known as electroplating.
Float Test
If your jewellery immediately sinks, it is likely solid gold. If it floats, it is not real gold because solid gold is denser than water. However, keep in mind that gold plated jewellery can contain heavy base metals that also sink, meaning this test works only to spot fake gold that floats.
Test Gold Using the Float Test
Take a cup or glass, fill it up with water, now bring the gold that you want to test. Drop it into this filled glass. If the gold floats, it is surely not real but if the gold sinks to the end of the glass then it is pure gold. The real gold will sink due to being a heavy metal.
Finally, we suggest both for silver and gold plated items, not to use abrasive substances such as lemon, vinegar, salt, parmesan, cola, because they tend to corrode the surfaces.
Lemon Juice
Lemon is naturally acidic, which helps remove the oxide layer on the jewelry easily. Mix equal parts of water and lemon juice. Soak the jewelry in this solution for 10 to 15 minutes. Gently scrub the jewelry with a rough cloth or toothbrush.
One study showed that when a 14K white gold ring was placed in common household bleach for 36 hours, the ring completely disintegrated! Small amounts of chlorine exist in tap water, too.
Using the Float Test
A cup of water is all you need for another important test. Any size piece of genuine gold will immediately sink to the bottom of any liquid. Imitation gold floats or hovers above the bottom of the container. In addition, real gold will not rust or discolor when wet.
The color still may suggest that it is a substitution or an alloy. If the jewelry you chose has a faint reddish tint to it, there is a chance that copper is in the alloy. If the color is faint, zinc or brass is added to the alloy. Also, if there is enough copper in the alloy, it can look the same as gold.
Q: Will Gold-Plated Brass Tarnish? A: Gold-plated brass will tarnish over time, but it will take longer than if the piece is made of pure brass. The gold plating protects the brass beneath it from tarnishing, but eventually, the gold itself will begin to fade, leaving the base metal susceptible to tarnishing.
Yes, gold-plated necklaces can fade over time. This is because the layer of gold plating is very thin, and as the jewelry is worn and exposed to elements like sweat, water, and chemicals, the gold plating can wear away.