How to Test Gold Jewelry in NZ?
Gold jewelry is valuable and so beautiful. But do you know how to confirm if the gold is real? There are several ways of checking your gold in New Zealand. You are buying, selling, or just curious whether your gold jewellery is genuine. These methods can check this for you. Here is How to test gold jewelry in NZ!
This guide covers every testing method available to NZ residents — from simple home checks you can do right now to the professional XRF testing that gives a definitive result. At TJ Handcrafted, our gold buyers team in Auckland and Houston, TX conducts professional gold testing free of charge for anyone who wants a confirmed answer on what they own.
Why test gold jewelry?
1. Authenticity
Gold is costly. Sadly, there is also fake gold. Testing will confirm whether it is real gold. In New Zealand, imported jewellery — particularly pieces purchased online, overseas, or at markets without certification — represents the highest risk category for misrepresented gold content. A piece stamped "18K" that is actually gold-plated brass is a form of consumer fraud, and testing is the only reliable protection. If you are unsure about a piece you already own, a professional test at TJ Handcrafted costs nothing and takes under five minutes.
2. Know Its Value
The carat value determines its price. Testing verifies this value. Understanding the exact karat is essential before selling — a 9K piece (37.5% pure gold) and an 18K piece (75% pure gold) of the same weight have dramatically different melt values. A seller who accepts a 9K offer on what is actually 18K gold has lost half the piece's intrinsic value in a single transaction. Testing before selling ensures you receive the right offer for the right metal.
3. Protect Against Frauds
Testing while buying or selling gold guards you against scams. The most common gold-related scams in NZ involve plated jewellery sold as solid gold, misrepresented karat markings (a piece stamped 18K that tests as 9K), and counterfeit hallmark stamps. All three are defeated by insisting on testing before any transaction. Any reputable seller or buyer will welcome testing — if a party resists or deflects a request to test the piece, that resistance is the most important data point in the interaction.
4. Keep the Peace of Mind
The quality of gold you possess removes the uncertainty. You can believe what you have. Peace of mind has a practical financial dimension too: knowing the exact karat and weight of your gold holdings gives you an accurate picture of their current value at any point in time. With gold prices near historic highs in NZD in mid-2026, many New Zealanders are discovering that inherited or long-held pieces are worth considerably more than they realised — and testing is the first step to understanding what you have.
Gold Purity
Pure gold is rarely 100% pure. It contains some other metals to strengthen it. It measures purity in karats, (K).
24K: Pure gold Soft and Costly.
18K: 75% gold, 25% other metals. Great for jewellery.
14K: 58.3% gold. Strong and commonly used.
9K: 37.5% gold. Cheap and hard.
In New Zealand, you'll see that jewelry is usually labelled with its karat rating. However, marks can be deceptive. That's why testing is essential!
Read more: Are gold nuggets pure gold?
5 Tools You Can Use to Test Gold
1. Gold Testing Kit
A gold testing kit contains acids for various karats. It's inexpensive and convenient to use.
2. Magnet
Gold is not magnetic. A quick magnet test can eliminate fakes.
3. Scale
Weigh your jewelry. Pure gold is dense and heavier than fake materials.
4. Loupe or Magnifying Glass
Examine the jewelry for markings. A loupe helps you see small details.
5. Professional Tools
Electronic gold testers or X-ray fluorescence machines may be used by professionals.
Testing Gold at Home
Step 1: Visual Inspection
Examine your jewelry closely. Inspect for any stamps or hallmarks that indicate its gold purity.
Hallmarks: These are tiny marks stamped on the jewelry, such as "24K," "18K," "14K," or numerical values like "375," "585," or "750."
Manufacturer's Mark: Some may bear the brand or logo of the jeweler, which may help verify authenticity.
Wear and Discoloration: Look for areas where wear is most evident, such as the edges or clasps. If another metal peeks through, it could be gold-plated rather than solid gold.
Note that some of the older or handmade pieces do not have these marks but are still genuine gold.
Step 2: Magnet Test
Gold is not magnetic, so this is a quick way to rule out fake gold made with ferrous metals.
How to Perform
Use a strong magnet, such as a neodymium magnet, for the test.
Hold the magnet close to your jewelry.
Results
Not Magnetic: This suggests the piece might be gold.
Magnetic: The piece likely contains iron or nickel, indicating it is fake or gold-plated.
Tip: Some fake gold pieces are non-magnetic, so combine this test with others for accuracy.
Step 3: Acid Test
The acid test is one of the most precise methods for checking gold purity. A gold-testing kit, available online or in jewellery shops, makes this very convenient.
Materials Needed
Gold testing stone
Different acids for each karat type
Gloves and protective apparel
Procedure
Clear an area: Perform the experiment in a well-ventilated area and with a glove on to avoid any contact with the skin.
Scratch the Gold: Rub the jewelry against the testing stone to ensure an observable scratch.
Add Acid: Place a few drops of the acid onto the scratch. Use an acid that is specific to the karat level being tested.
Observe the Reaction: Pure gold won't react to the acid, while fake gold or lower-purity metals will dissolve or react.
Step 4: Water Density Test
Gold is an extremely dense metal with a 19.3 g/cm³ density. This property makes the water density test a great home experiment.
Materials Needed
A kitchen scale
A container of water
A ruler or graduated cylinder
Instructions
Weigh the Gold: Write down the weight of your jewelry in grams.
Measure Water Volume: Fill a container with a measured amount of water. Write down the starting volume.
Submerge the Gold: Place the gold piece in the water and measure the new volume.
Calculate Density
Use this formula:
Density = Weight of Gold / Water Displacement
Results
19.3 g/cm³: Pure gold.
Lower Density: Probably gold alloy or fake material.
Tip: Remove all non-gold parts, like stones or clasps, for accurate results.
Step 5: Ceramic Scratch Test
This test employs an unglazed ceramic plate to check for gold.
Steps
Locate an unglazed ceramic tile or plate.
Rub the gold piece on the ceramic surface.
Observe the colour of the streak.
Results
Gold Streak: Genuine gold leaves a yellow streak.
Black Streak: Indicates fake gold or other metals.
Note: Be careful, as this test may scratch your jewelry.
Step 6: Inspect Under a Magnifying Glass
Use a magnifying glass or loupe to closely look at the jewelry.
Edges and Corners: Check for uneven plating or wearing.
Fakes: There may be bubbles or finishes that appear rough.
Read more: What is scrap gold worth?
Combine Results
To get an accurate conclusion, use combinations of tests. No individual test is definitive. Example:
A non-magnetic result and a positive acid test indicate that it is likely actual gold.
Water density and eye inspection can confirm purity levels together.
If you still don't get a definitive answer, then proceed to professional testing for a clear answer.
Seek Professional Opinion
If not sure, then get a professional opinion. Jewelers and pawnshops usually offer free testing services.
What to Expect from Professionals
Positive results
Professional use of appropriate equipment
Professional judgment on what the value of the sample is
Who to find in NZ
Local Jewelers
Precious metals dealers
Gold Testing Services in NZ like TJ Gold
Read more: Is gold jewelry a good investment?
Final Thoughts
How to test gold jewelry in NZ? - Testing gold jewelry is important in New Zealand. Whether at home or with a professional, it safeguards your investment. Using simple tools and methods, you can confidently verify your gold's authenticity and value.
In case of uncertainty, consult an expert. Knowing your stuff can ensure buying and selling gold jewelry without fear!
Frequently Asked Questions
What is the most accurate way to test gold jewellery in NZ?
XRF (X-ray fluorescence) testing is the most accurate method — it provides the exact gold percentage and full elemental analysis non-destructively in under five minutes. It is the professional standard used by gold buyers, refiners, and jewellers worldwide. At TJ Handcrafted's gold buyers service in Auckland, XRF testing is available free of charge. For home testing, the acid test is the most reliable option — more accurate than the magnet, density, or ceramic tests — but requires careful chemical handling and will scratch the piece.
Can I test gold jewellery at home without damaging it?
Yes — the visual inspection, magnet test, and water density test are all non-destructive. The ceramic scratch test and acid test both involve contact with the piece's surface and will cause minor visible marks if not done carefully on an inconspicuous area. For pieces with sentimental or significant financial value, the safest approach is the non-destructive home tests first, followed by professional XRF testing rather than risking surface damage. XRF is free at TJ Handcrafted — there is no reason to risk scratching a valuable piece when professional testing is available at no cost.
What do the hallmark numbers on gold jewellery mean in NZ?
Hallmark numbers represent the gold content in parts per thousand: 375 = 9K gold (37.5% pure), 585 = 14K (58.5% pure), 750 = 18K (75% pure), 916 or 917 = 22K (approximately 91.6% pure). These are stamped on genuine solid gold jewellery and are legally required in New Zealand for pieces sold as gold. For a full guide to reading and understanding gold hallmarks, read: What is 585 gold?
