Gold Karat Purity Chart

You have the piece in your hand, a chain or a ring, and the only thing between you and its value is a tiny mark you need a loupe to read, which you can identify using a gold karat chart.It tells you exactly what percentage of that metal is actually gold, and that number sets the price. Before you weigh anything or call a buyer, decode what that stamp means. The difference between a 10K and an 18K piece of the same weight is the difference between a low offer and a serious one.

Gold purity is measured two ways, and you will see both on jewellery and in pricing. Karat (K) is the older system, a fraction of 24, where 24K is pure gold. Fineness is the modern European system, parts per thousand. The table below gives the conversion you need to check any offer you receive. A buyer will quote you a percentage of melt, and you need to know what that percentage is a percentage of.

Karat	Percent Gold	Fineness (Parts per Thousand)
24K	99.9%	999
22K	91.7%	916
18K	75.0%	750
14K	58.3%	585
10K	41.7%	416
9K	37.5%	375

Hallmarks are the official stamps that verify fineness, and they are not all the same. The UK Assay Office, operating under the Hallmarking Act 1973, requires an official hallmark on most gold items sold in the UK. The fineness marks it recognises are 375, 585, 750, 916, 990, and 999 parts per thousand. The US has no such national system. The Federal Trade Commission (FTC) enforces standards for stamped karat, allowing a tolerance of ±0.5K (16 CFR 23.4). That means a piece stamped 14K in the US could legally be as low as 13.5K or as high as 14.5K. Country marks are the responsibility of the origin country's assay office, not a purity claim by itself.

The letters after the karat, like KT or KP, matter. KP means 'karat plumb', a US designation that the actual gold content is at least the stamped karat, with no tolerance for being under. KT is simply an alternative spelling of karat, and it carries no special guarantee. When you read a stamp like 585, you are reading the fineness in parts per thousand, which is the same as 14K. A stamp of 750 is 18K. A stamp of 916 is 22K, common in some high-end or traditional pieces.

If you do the math, 14 divided by 24 is 58.33 percent, which rounds to 583 parts per thousand. But the hallmarking conventions in Europe and the UK do not use 583. They use 585, which is the standard fineness mark for 14K gold under the Hallmarking Convention (Vienna Convention) and the UK Assay Office. The reason is standardisation: the convention set the allowable fineness marks at 375, 585, 750, 916, 990, and 999. 583 is not on that list. A piece stamped 585 is not more pure than a piece stamped 583; it is the same alloy, just marked to a different standard. When you see 585 gold, it is 14K gold, period. The 585 figure is the one used in the gold purity chart you will see in any refiner's or assayer's literature, so do not be confused by the older US mark of 583 that occasionally appears on vintage pieces.

No. A 14K stamp is a claim, not a guarantee of exact purity. In the US, the FTC allows a tolerance of ±0.5 karat. A piece stamped 14K can be as low as 56.3% gold (13.5K) and still be legally sold as 14K. In the UK and EU, the assay office enforces a different rule: the actual fineness must be at least the marked fineness. The tolerance for fineness marks is set by the Hallmarking Convention, and it allows a negative tolerance of 5 parts per thousand for 585 gold. That means a 585 mark can be as low as 580 parts per thousand, or 58.0% gold, and still pass.

When you are selling scrap, you will not know the exact purity without testing, but you can assume the piece is close to the mark, not exactly on it. For a 14K piece, the difference between 58.3% and 56.3% on a 5-gram item is about 0.1 grams of gold. That is why a buyer who tests the piece and finds it slightly under the mark will adjust the price. Do not assume your 14K piece is exactly 58.5% gold. Assume it is between 56% and 58.5%, and weigh the value accordingly.

Karat and carat are not the same word. Confusing them is a common error that has no effect on your gold's value but does affect how you read a scale. Karat (K) with a K measures gold purity, as in 14K or 18K. Carat (ct) with a C measures gemstone weight, where one carat equals 0.2 grams. A diamond of one carat weighs 0.2 grams, but a gold piece of one karat is 1/24th pure gold. When you see a stamp like '14K' it is purity; when you see '1 ct' on a ring, it is the stone. On a scrap gold calculation, you only care about karat. But if you are weighing a piece with stones, you need to subtract the stone weight, and that is where carat matters. A piece with a 0.5 carat diamond has a stone that weighs 0.1 grams, which you should not count as gold. This is one of the failure modes in scrap gold selling: not subtracting stone weight overstates your gold's weight and the melt value you think you should get.

When you sell scrap gold, the price you are offered is a percentage of the melt value. The melt value is calculated with a simple formula: weight in troy ounces multiplied by fineness (as a decimal) multiplied by the spot price of gold. The spot price is the going rate for one troy ounce of pure gold, and it is set by the global market, not by the buyer. You will never be offered the spot price. You will be offered a percentage of melt value, typically 60% to 80% for 10K to 14K pieces, less for lower karats and more for higher karats. The buyer has to refine the gold, pay their overhead, and make a profit. Those costs come out of the melt value.

The formula for fineness is straightforward: 10K is 0.4167, 14K is 0.5833, 18K is 0.75, and 22K is 0.9167. Multiply your weight in grams by 0.03215 to convert to troy ounces, because there are 31.1 grams in a troy ounce, not 28.35. That conversion error is the most common mistake in scrap gold, and it overstates your value by 9.7% if you use the wrong ounce.

14K gold is the workhorse of the US jewellery market. It is the karat you will most often find in a scrap lot. It is 58.3% gold, alloyed with copper, silver, and zinc to give it strength, because pure gold is too soft for daily wear. When you see a stamp that says 14K or 585, you are looking at the same thing.For a seller, 14K is a good middle ground: it has more gold content than 10K, so it has more value per gram, but it is more common than 18K, so there are more pieces to buy. The 14K gold purity is not a mystery. It is 58.3%, and that is the number you use in the melt value calculation. A 5-gram piece of 14K gold has a melt value that is your starting point. The buyer's offer will be 60% to 80% of that.

If you are in the US and you see a stamp that says 585 or 750, you are looking at European or UK hallmarks. They mean the same as 14K and 18K respectively. The 585 gold meaning is 58.5% pure gold, and the 750 gold meaning is 75.0% pure gold. These marks come from the Hallmarking Convention, which standardises fineness marks across participating countries. A piece stamped 585 is legally 14K, and a piece stamped 750 is 18K. Do not be confused by a piece that has both a karat mark and a fineness mark, like '14K 585', which is redundant but legal. When you sell scrap, you can treat these marks as identical to their karat equivalents. The only difference is that some US buyers are less familiar with the fineness marks and may try to pay you less, claiming they are not standard. That is a negotiation point, not a purity issue. Know your marks, and you will not be taken advantage of.

The melt value is not what you receive. Anyone who tells you otherwise is selling you something. The payout percentage is the portion of melt value a buyer pays, and it varies by buyer type. A pawn shop might pay 50% to 60% of melt value. A mail-in refiner might pay 70% to 80%. A jewellery buyer at a show might pay 60% to 70%. The difference is their costs: a storefront has rent and staff, a mail-in operation has shipping and insurance, and a refiner has the cost of melting and assaying. The highest payouts are usually from refiners who buy in bulk, but they require a minimum weight and you have to wait for payment. The lowest are from 'we buy gold' kiosks, which are known for offering far below melt. The FTC advises consumers to verify the buyer's license, get a written quote, and compare offers. The practical advice is to get at least three quotes and not accept the first offer. The spot price is the anchor, and the payout percentage is the negotiation. Know the current spot price before you walk in. Do not let a buyer quote you a price that is a percentage of something other than the current spot.

Dental gold is a trap for the unwary seller. Most dental work is not high-karat. Dental gold is often 10K to 16K, and it is frequently a high-noble alloy that contains gold, palladium, and silver, not pure gold. A crown that looks gold might be 60% gold and 20% palladium. The palladium has its own value, but it is not the same as gold. When you sell dental gold as scrap, you are paid for the gold content only. The palladium may or may not be credited, depending on the buyer. Some dental alloys are marked with a number like '14K' or a manufacturer's stamp, but many are not. If a crown has no stamp, assume it is low-karat until proven otherwise. The melt value of a typical dental crown is a few dollars, not a windfall. The refining loss is high because of the other metals. Do not expect to retire on your bridgework.

Before you sell, you need an accurate weight. Not all scales are created equal. For trade, a scale must be NIST Handbook 44 Class II or better, but most sellers do not have one. That is fine for a few pieces. A consumer scale that reads to 0.01 grams is adequate, but you must calibrate it with a known weight, like a US coin. A nickel weighs 5.00 grams, and a penny weighs 2.50 grams. Use those to check your scale. If your scale reads 5.05 grams on a nickel, it is off by 1%. That is not a huge loss, but it adds up over a lot of pieces.

You also need to test for gold-filled or plated items. A piece that looks solid may be mostly base metal. A magnet test is a quick way to rule out steel or iron, but it will not tell you if a piece is gold-filled. The only reliable test is acid testing or an electronic tester, and most sellers do not have those. The failure mode is selling a gold-filled piece as solid gold, which overstates your value by 90% or more. If you are not sure, take it to a jeweller for a test. Be prepared to pay a small fee. The alternative is to accept the buyer's test, but that puts you at their mercy.

You do not need a buyer to tell you what your gold is worth. A scrap gold calculator is a simple tool that does the melt value math for you. You can do it by hand in under a minute. Take your weight in grams, divide by 31.1 to get troy ounces, multiply by the fineness (0.583 for 14K), and multiply by the current spot price. For example, a 5.0-gram piece of 14K gold is 5.0 / 31.1 × 0.583 × the spot price. That is the melt value. A fair offer is 60% to 80% of that. If a buyer offers you less than 50% of melt value, walk away. If they offer more than 80%, be suspicious. They are likely making it up in the weight or the purity.

The spot price changes every few seconds, but you do not need a live feed. A price from a few hours ago is close enough for a negotiation. The mistake people make is using the spot price of gold per ounce without converting to troy ounces, which overstates the value by 9.7%. Another mistake is using the karat stamp at face value. The FTC allows a 0.5K tolerance, so your 14K piece could be 13.5K. When you calculate the value, use the lower end of the range to see what the worst case is, and the higher end to see the best.

The most common failure in selling scrap gold is not knowing what you have. A piece stamped 14K that is actually gold-filled will have a layer of gold bonded to a base metal. The stamp alone will not tell you. Gold-filled items are marked with something like '1/20 14K GF' or '14K GF'. That means the gold content is 1/20th of the total weight, not the full karat. A 10-gram gold-filled piece contains at most 0.5 grams of gold. Another failure is using the wrong ounce. There are 31.1 grams in a troy ounce, but many people use the avoirdupois ounce of 28.35 grams, which overstates the value by 9.7%. A 10-gram piece is 0.3215 troy ounces, not 0.3527. The same confusion applies to pennyweight: 1 pennyweight (dwt) equals 1.555 grams, so a 10-dwt piece is 15.55 grams, not 10 grams. If you quote a weight in grams but the buyer quotes in pennyweight, you will be confused.

The final failure is not testing for plated items. Gold-plated jewellery has a thin layer of gold over base metal, and it has no karat stamp. A magnet test will not catch it, because the base metal might be brass or copper, which is not magnetic. The only way to be sure is to cut the piece or use acid. You should not do that to a piece you plan to sell as gold. If you are not sure, sell it as 'unknown'. Let the buyer test it, but expect a low price.

It is late, you have the gold in your hand, and the pawn shop closed hours ago. You could use a coin-operated machine in a grocery store. Those pay 40% to 60% of melt value. You will lose money you cannot get back. Do not use the machine. Instead, put the gold in a safe place. Write down the weight and the karat stamps you can see. Wait until morning. The spot price of gold is set during market hours, and it moves. If you sell at 1 a.m., you are selling at the same spot price as during the day, but the buyer's offer is based on their costs. A machine's offer is fixed to pay the machine's owner, not you.

The alternative is to sell online to a mail-in refiner. That requires a prepaid shipping kit, which you do not have at 1 a.m., and it takes days to get paid. The better play is to wait a few hours. Go to a local buyer during business hours and negotiate. If you are in a hurry for cash, sell something else. A rushed gold sale is a bad gold sale. The one thing you should never do is sell to a 'cash for gold' kiosk without knowing the current spot price. Those machines are calibrated to pay a fixed percentage that is far below what you can get from a person.