Real gold is stamped with numbers indicating its purity, typically a three-digit number like 999 (24k), 750 (18k), 585 (14k), or 417 (10k), representing the percentage of pure gold (e.g., 99.9%, 75%, 58.5%, 41.7%), or sometimes the karat (k) directly, with 24k being the purest (999) and lower numbers indicating more alloy for strength. These hallmarks are found in discreet spots like inside rings or necklace clasps.
The most commonly used markings on gold are the following: 999 = 24 carat. 916 = 22 carat. 750 = 18 carat.
Gold stamp numbers
You can also see other numerals like 999, 750, or 585 in place of karats. For example, 999 represents pure gold, while 750 denotes 18K gold. Silver is generally stamped with numbers instead of karats to denote purity: 999: Fine silver, fineness 99.9%.
Look for letter markings next to the karat stamp
Sometimes a karat stamp will be followed by other letters such as P, GP, GF, GE or GEP, HGE, or RGP. Let's decode their meanings below. P: A “P” mark indicates the piece is plumb, meaning the gold purity is exact. Example: '10KP' is exactly 41.7% gold.
In India, a gold hallmark is issued by the Bureau of Indian Standards (BIS) and includes the BIS logo, a purity grade such as 916 for 22K gold, and a unique six-digit alphanumeric Hallmark Unique Identification (HUID) number. The bureau certifies the fineness and purity of the gold jewellery with hallmarking.
A piece of gold jewelry is typically engraved with a hallmark; most real gold has a hallmark that shows its purity which is its karat. Karat is the unit that is used to measure the purity of gold. When the karat is higher, the piece of gold is purer. The most common karats are 10k, 14k, 18k, 22k, and 24k.
The standard mark denotes the purity of the metal and consists of three numbers to show the precious metal content as parts per thousand, within a shaped stamp. The stamp for gold items is a rectangle that has had its corners removed, giving it eight sides.
Gold is a chemical element with symbol Au and atomic number 79.
One of the easiest ways to determine if a piece of gold is real is to look for hallmarks. Most authentic gold items will have a stamp that indicates their karat value, which tells you the purity of the gold. Common Hallmarks: Look for stamps like 10K, 14K, 18K, or 24K. The higher the number, the purer the gold.
As of early January 2026, the gold price in Australia per gram (24k) fluctuates, but you're looking at roughly AUD $215 to $265 per gram for spot/general, with actual buy/sell prices varying by dealer and product, such as around $214.81/gram on Market Index or higher for retail bars from places like ABC Bullion. Always check live dealer sites like ABC Bullion or Melbourne Gold Company for the most current buy/sell rates for specific products.
Hallmarks are generally set in a horizontal line, slightly less than 1.5mm in height. The most common order of hallmarks from left to right is; sponsor, fineness (purity) and assay office. Other hallmarks after these are optional.
Hallmark Unique Identification (HUID) number is a six digit code consisting of numbers and letters. A unique HUID will be assigned and laser inscribed to every piece of jewellery at the time of hallmarking. This HUID, along with more details, are stored in BIS database for traceability.
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.
How to identify real gold
Every hallmarked gold ornament carries a unique HUID number, which acts like a serial code. You can verify this number through the BIS Care app or the BIS website by entering it in the search field. The system will display the details of purity, weight, and registered jeweller.
Gold is element 79 and its symbol is Au.
What Are the Methods to Check if Your Gold Jewellery Is Real?
Some of the most common markings found on gold jewelry items include karat stamps, hallmarks, and assay marks. For instance, karat marks usually combine letters and numbers, but other letters often appear alongside the karat mark. These purity marks offer deeper insight into the nature of the jewelry piece.
The carat (UK spelling, symbol c or Ct) or karat (US spelling, symbol k or Kt) is a fractional measure of purity for gold alloys, in parts fine per 24 parts whole.
A missing hallmark doesn't automatically mean it's fake. Some older or custom-made jewelry may not have a visible stamp. If your necklace passes other tests, it could still be real gold. A jeweler can confirm its authenticity.
417 gold is also known as 10 karat (10K) gold, and it means that the gold is 41.7% pure gold, with the remaining 58.3% made up of other metals. The 417 marking is commonly found on lower-end jewelry pieces.