999, for example, is the purist amount, essentially 24 karat gold with a 99.9999% purity. On the other hand, 750 is indicative of a 75% purity level, better known to most as 18 karat gold. The 3-digit stamp sequence generally gets identified as follows: 999.9 or 999 – 24 karat gold. 995.
Here are some of the most common jewelry hallmarks: Karat (KT or K) - Indicates the purity of gold, the higher the karat number, the purer the gold. Fine Silver (FS) - Indicates that a piece consists of at least 99.9% pure silver. Sterling Silver (SS) - Indicates that a piece consists of at least 92.5% pure silver.
In Australia there has never been and still isn't a silver or gold marking required on items. It is of course in the best interest of the jeweller to mark their jewellery and many did. Silver pieces are often only marked STG SIL, STG SILVER or Sterling Silver.
The best way to tell if the gold you are purchasing is real is to look for a hallmark. This is a small stamp indicating the gold's karat weight. Different locations use different measurements. In the U.S., the hallmark number is a fraction of 24.
The stamp will typically be on the clasps of jewelry. Some counterfeit gold will have a karat stamp on it, but rarely have a manufacturer's name.
Gold is a very soft metal, so scratching it with a hard object like ceramic will leave a golden or a yellowish streak. On the other hand, fake gold is often made of metals that are darker in color, so you'll see a dark streak instead.
By law, gold jewelry sold by a vendor must have a stamp of the piece's purity, so finding a stamp is a good sign! If you can't find a stamp, it's possible it wore off with time, or was sold before the law was passed. Don't worry if there is no stamp to be found, you can always consult an expert!
The Australian industry is highly regulated which means that your jewellery, whether it is gold, silver or platinum, should have a stamp mark indicating the gold content.
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.
Here are a few stamps or markings that you may see on your jewelry: A Number Followed by a K: If you see a 14K, 18K, or 24K on the inside of your ring or on the clasp of your jewelry and no other markings, chances are your jewelry is solid gold. GP: This stands for Gold Plating.
Gold Purity Marks
Purity marks on gold jewelry will consist of a two-digit number followed by the letter “k,” or a three-digit number. The letter “k” refers to karats, where pure gold is composed of 24 karats (24k).
'375' gold is just one of many different types of hallmarks. If a gold product bears the hallmark '375', then your gold has been tested and classed as 9 carat or 37.5 per cent pure.
When the hallmark is found on gold jewelry, most people think it means that the piece of jewelry contains 92.5% gold. However, 925 gold jewelry, also referred to as gold vermeil or costume jewelry, is actually sterling silver that has had gold plated onto it.
You can't buy, hold or sell gold unless it is a legitimate part of your trade or in the form of jewellery. However, the phrasing of the law is all around physical as it mentions “delivery” of gold in your “possession”.
Gold prospecting and fossicking opportunities in Australia's Golden Outback draw people from far and wide. To prospect in Western Australia, you require a Miner's Right for each person in your party. This gives you authorisation to prospect on: Unoccupied crown land that is not covered by a granted mining tenement.
The fineness mark determines the purity of gold. Sometimes fineness of gold is marked as 375, 585, 750, 916, or 999, stating the number of gold parts per thousand. You may recognize the fineness gradation in carats – the commonly used standards are 9ct, 14ct, 18ct, and 22ct.
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.
Hallmarks. Gold must be stamped with a hallmark that tells the purchaser what karat the gold is. 18- karat gold will have a small stamp on the inside of the jewelry that reads 18k.
The jeweller cannot sell a gold item without proper hallmarking but has the option to melt it and make a new one with the latest six-digit hallmark. Hence, as per the new rules, any jewellery item bought from now on will come with a purity certification.
What to do: Hold the magnet up to the gold. If it's real gold it will not stick to the magnet. (Fun fact: Real gold is not magnetic.) Fake gold, on the other hand, will stick to the magnet.
The Acid Test
Drop a small amount of liquid nitric acid on that scratch and wait for a chemical reaction. Fake gold will immediately turn green where the acid is. Gold-over-sterling silver will become milky in appearance.
Gold purity is measured in karats with 24 karats representing the highest value. Gold jewelry marked "750" or "18k" indicates a blended metal consisting of 75% gold and 25% other alloys or elements. Likewise, a "585" or "14k" imprint indicates a gold content equal to 58.5% of the whole.