Why is 14K gold the most common in American jewelry?

14K gold is durable enough for daily wear (the alloy metals add hardness that pure gold lacks), looks like gold, and is priced for the broader market. 24K and 22K are too soft for everyday rings and bracelets and would deform with use. 18K is harder than 22K but softer than 14K, used mostly for higher-end jewelry. 10K is the minimum karat the United States allows to be called gold; it is hard and cheap but contains less gold than other countries permit.

Gold Karat Guide: 10K vs 14K vs 18K vs 22K vs 24K

Q: What is the difference between 10K, 14K, 18K, 22K, and 24K gold?

10K gold is 41.7 percent pure gold (10/24), commonly used in lower-cost American jewelry. 14K is 58.3 percent pure gold (14/24), the most common gold purity in the United States for fine jewelry. 18K is 75 percent pure gold (18/24), standard for higher-end European and American jewelry. 22K is 91.7 percent pure gold (22/24), common in Indian, Middle Eastern, and traditional Asian jewelry. 24K is 99.9 percent pure gold, almost exclusively used in bullion and investment-grade bars and coins.

Q: What gold hallmarks should I look for?

American jewelry typically stamps the karat number followed by K (10K, 14K, 18K, 22K, 24K). European jewelry uses the parts-per-thousand stamp: 417 for 10K, 585 for 14K, 750 for 18K, 916 for 22K, 999 for 24K. UK and Commonwealth countries use additional hallmarks including the assay office mark, sponsor mark, and date letter. Italian jewelry often stamps 750 plus a maker mark. Look on the inside of rings, the back of clasps on chains, and the back of pendants and earrings.

Q: How do I test if gold is real?

The most reliable non-destructive test is X-ray fluorescence (XRF), which reads the metal composition to within 0.5 percent in seconds. Acid testing with nitric acid drops on the gold determines karat but leaves a small mark. The magnet test rules out ferrous fakes (real gold is not magnetic) but does not confirm karat. The skin reaction test (real gold should not turn skin green) is unreliable. The scratch-and-compare test with a touchstone requires experience. For sellers, on-site XRF at a reputable buyer is the gold standard.

Q: What about white gold and rose gold karats?

White gold and rose gold are still karated by the same standard as yellow gold. The karat reflects gold content only, not color. White gold uses palladium, nickel, or silver as the alloy to create the color. Rose gold uses copper. So 18K white gold is still 75 percent pure gold; the remaining 25 percent is what changes the color. Rhodium plating is often added to white gold for a brighter white finish, but it wears off over time.

Q: Can gold be sold without a karat stamp?

Yes. Many antique and vintage pieces predate modern hallmarking standards. Some imported jewelry is unstamped. Some stamps have worn off. We test unstamped gold with XRF or acid and price off the actual measured karat content. Real gold sells whether it is stamped or not; the test confirms what you have.

Gold karat is the measure of how much pure gold is in a piece of jewelry or bullion. The karat scale runs from 1 to 24, with 24-karat representing 100 percent pure gold. Every karat is 1/24th of the total metal. This guide explains what each karat means, what hallmarks to look for, how to test purity, and how karat affects what your gold is worth in 2026.

If you are selling gold in Miami, the buyer should be able to test the karat on site (typically with X-ray fluorescence, or XRF), show you the live spot price for gold, and explain how the karat translates to the melt value. If a buyer cannot or will not do this, that is a signal to walk away. CJ William prices every gold purchase off live spot at the moment of transaction, with the math shown. See the We Buy Gold in Miami page for the buying process.

The Karat Scale Explained

Karat (abbreviated K or kt) measures the proportion of pure gold in an alloy out of 24 parts. The number tells you how many parts out of 24 are pure gold. The remaining parts are other metals (typically copper, silver, zinc, palladium, or nickel) added for hardness, color, and workability.

Note: Karat (gold purity) is different from carat (gemstone weight). Same pronunciation, different meanings.

The Common Karats: 10K, 14K, 18K, 22K, 24K

Karat	Gold Content	Parts Per Thousand Stamp	Common Use
10K	41.7 percent pure gold	417	Lower-cost American jewelry, class rings, mass-market chains
14K	58.3 percent pure gold	585	Most common American fine jewelry, engagement rings, wedding bands
18K	75 percent pure gold	750	Higher-end European and American jewelry, signed designer pieces
22K	91.7 percent pure gold	916	Indian, Middle Eastern, and traditional Asian jewelry
24K	99.9 percent pure gold	999	Bullion bars, investment coins, occasional Asian jewelry

10K Gold (41.7 Percent Pure)

The minimum karat the United States allows to be sold as gold. Common in lower-cost American jewelry, class rings, and mass-market chains. Hard and durable due to the high alloy content, but contains less gold than most other countries permit. Stamps: 10K, 10KT, 417.

14K Gold (58.3 Percent Pure)

The most common gold purity in American fine jewelry. Engagement rings, wedding bands, tennis bracelets, and most US-made gold jewelry is 14K. Balances durability (for daily wear) with gold content. Stamps: 14K, 14KT, 585.

18K Gold (75 Percent Pure)

The standard for higher-end European and American fine jewelry. Cartier, Bulgari, Van Cleef, Tiffany & Co., and most signed designer jewelry uses 18K. The high gold content gives a richer color than 14K but is softer. Stamps: 18K, 18KT, 750.

22K Gold (91.7 Percent Pure)

Common in Indian, Middle Eastern, Pakistani, and traditional Asian jewelry. Rich yellow color closer to pure gold. Softer than 18K and more prone to scratching, so often reserved for pieces that are not worn daily. Stamps: 22K, 22KT, 916.

24K Gold (99.9 Percent Pure)

Effectively pure gold. Almost exclusively used in investment bullion (bars and coins from PAMP, Valcambi, Credit Suisse, Royal Canadian Mint, Perth Mint, and others) and the occasional traditional Asian piece. Too soft for daily-wear jewelry. Stamps: 24K, 24KT, 999, 999.9.

Hallmarks: What to Look For

Gold jewelry is typically stamped in inconspicuous locations: the inside of a ring band, the back of a chain clasp, the back of a pendant bail, the post of an earring, or the underside of a watch case. The stamp tells you the karat (and sometimes the maker, country of origin, and assay office).

American Stamps

American jewelry uses the karat number followed by K or KT: 10K, 14K, 18K, 22K, 24K. Older American pieces may stamp KT instead of K. Sometimes accompanied by a maker mark.

European Stamps (Parts Per Thousand)

European jewelry uses the parts-per-thousand notation: 417 for 10K, 585 for 14K, 750 for 18K, 916 for 22K, 999 for 24K. The number is sometimes accompanied by a maker mark, country mark (Italy stamps 750 plus a province number in a hexagon), and assay office mark.

UK and Commonwealth Hallmarks

UK jewelry from the assay office system uses a multi-mark hallmark: the sponsor mark (maker), the standard mark (purity), the assay office mark (London, Birmingham, Edinburgh, Sheffield), and a date letter. UK 18K reads 750 with the standard mark.

Indian and Middle Eastern Stamps

Indian jewelry frequently stamps 22K, 22KT, or 916 plus the BIS (Bureau of Indian Standards) hallmark. Middle Eastern jewelry uses 916, 875, or 750 depending on the region. Saudi and Kuwaiti jewelry is often 21K (875).

When the Stamp Is Worn or Missing

Many antique and vintage pieces predate modern hallmarking standards. Some imported jewelry is unstamped. Some stamps have worn off from decades of daily wear. Unstamped gold can still be tested and sold. XRF or acid testing confirms the karat regardless of the original stamping.

How to Test Gold Karat

XRF (X-ray Fluorescence) Testing

The gold standard for non-destructive testing. An XRF spectrometer reads the metal composition to within 0.5 percent in seconds without damaging the piece. Used by professional buyers, refiners, and gemological laboratories. CJ William tests every piece of gold on XRF in our Surfside showroom.

Acid Testing

A drop of nitric acid of varying concentrations is applied to a small inconspicuous area or to a scratch on a touchstone. The reaction (or lack of reaction) indicates the karat. Reliable when done by experienced testers but leaves a small mark.

Magnet Test (Ruling Out Fakes)

Real gold is not magnetic. If a piece is attracted to a magnet, it contains ferrous metal and is either gold-plated or a base-metal fake. The magnet test rules out fakes but does not confirm karat.

Tests That Do Not Work

The skin reaction test (claiming real gold should not turn skin green) is unreliable; many factors cause skin discoloration. The bite test (gold should be soft enough to dent) is destructive and uninformative. The float test (gold should sink) only rules out hollow fakes.

How Karat Affects the Price When Selling Gold

Per gram, higher karat gold is worth more because it contains more pure gold. The melt value of any piece is calculated by multiplying the weight (in grams), the purity (as a decimal), and the live gold spot price (per gram). For example, a 10-gram 18K piece at $80/gram spot:

10 grams × 0.750 (18K purity) × $80/gram = $600 melt value
The buyer offers a percentage of this melt value, typically 92 to 95 percent on investment bullion and 80 to 90 percent on wearable jewelry, adjusted for refining costs.

For signed designer or antique jewelry, the maker premium or period premium can be many times the melt value. A signed Cartier or Tiffany 18K piece is almost always worth more as the intact piece than as melted gold, which is why selling to a buyer who knows the secondary market matters more than selling to a melt-only buyer.

Frequently Asked Questions

What does karat mean for gold?

Karat is the unit used to describe the purity of gold in jewelry. The karat scale runs from 1 to 24, with 24-karat representing 100 percent pure gold. Each karat represents 1/24th of the total metal. Karat is not the same as carat, which is the unit of weight for gemstones.

What is the difference between 10K, 14K, 18K, 22K, and 24K gold?

10K is 41.7 percent pure gold. 14K is 58.3 percent. 18K is 75 percent. 22K is 91.7 percent. 24K is 99.9 percent (effectively pure). Higher karat means more gold content but softer metal.

What gold hallmarks should I look for?

American jewelry: 10K, 14K, 18K, 22K, 24K. European: 417, 585, 750, 916, 999. UK: assay office hallmark stack. Indian: 916 with BIS mark. Look inside ring bands, on chain clasps, and on the back of pendants and earrings.

How do I test if gold is real?

XRF (X-ray fluorescence) is the most reliable non-destructive test. Acid testing confirms karat but leaves a small mark. The magnet test rules out ferrous fakes but does not confirm karat. Avoid the skin-green test and bite test, which are unreliable.

Which gold karat is worth the most?

Per gram, 24K is worth the most (most gold per gram). Per piece, the value depends on more than karat: maker, design, condition, stones, and current secondary market demand. A signed 18K Cartier piece is almost always worth more than its melt value.

Why is 14K the most common in American jewelry?

14K balances durability for daily wear with gold content. 24K and 22K are too soft for everyday rings. 10K is the US legal minimum to be called gold but contains less gold. 14K is the practical American compromise.

What about white gold and rose gold karats?

White and rose gold are karated identically to yellow gold. The karat reflects gold content only, not color. White gold uses palladium, nickel, or silver as the alloy. Rose gold uses copper. 18K white and 18K yellow contain the same percentage of pure gold.

Can gold be sold without a karat stamp?

Yes. Antique and worn pieces are often unstamped. XRF or acid testing confirms the karat regardless of original stamping. Real gold sells whether stamped or not; the test confirms what you have.

Selling Gold in Miami

CJ William buys gold in every karat, every form. XRF testing in our Surfside showroom. Live spot pricing. Same-day cash for transactions under $25,000, same-week wire for any size.

We Buy Gold in Miami

Call (347) 510-0668

This guide is part of the CJ William Knowledge Library. See also Silver Hallmark Guide, Platinum Identification Guide, Hermès Birkin Authentication Guide, Diamond Certification Guide, Watch Reference Number Guide, Antique Silver Identification Guide, Luxury Asset Liquidation in Miami, We Buy Gold, We Buy Silver, and We Buy Platinum in Miami. CJ William, 9573 Harding Avenue, Surfside, FL 33154.