What Is a Karat in Gold?
A karat measures gold purity — 24K is pure gold, 18K is 75% pure, 14K is 58.5% pure. Compare every grade below.
Shopping now? Compare 14K vs 18K gold to choose the right purity for your budget and lifestyle.
A karat (abbreviated K or KT) is a unit that measures how much of a gold item is pure gold. Pure gold is 24 karats — so 18K gold is 18 out of 24 parts gold (75% pure), and 14K gold is 58.5% pure gold.
Volume visualization
Each droplet = same volume. Gold (19.3 g/cm³) is much denser than silver/copper (≈10.5 g/cm³), so other metals need far more droplets to represent the same weight.
Based on a 10g example · 1 gold droplet = 0.1g gold · Other droplets density-corrected by volume
8K | 33.3 wt%
8 Karat / 333
9K | 37.5 wt%
9 Karat / 375
10K | 41.7 wt%
10 Karat / 417
14K | 58.3 wt%
14 Karat / 585
18K | 75.0 wt%
18 Karat / 750
20K | 83.3 wt%
20 Karat / 833
22K | 91.6 wt%
22 Karat / 916
24K | 100.0 wt%
24 Karat / 999
Gold purity at a glance
Each bar shows how much is pure gold (yellow) vs other metals (grey)
Each karat in detail
Common use: Older European jewelry, fashion jewelry
Common use: Common in UK, Australia, Norway
Common use: Budget jewelry, children's jewelry
Common use: Everyday jewelry, most popular in US & Norway
Common use: Fine jewelry, engagement rings
Common use: Middle Eastern jewelry
Common use: High-end jewelry, Indian bridal gold
Common use: Gold bars, coins, investment gold
Hallmark reference
Look inside your jewelry for these stamps — they tell you exactly what you have:
| Hallmark | Karat | Gold % | Common in |
|---|---|---|---|
| 333 | 8K | 33.3% | Norway, Germany (older) |
| 375 | 9K | 37.5% | UK, Australia, Norway |
| 417 | 10K | 41.7% | USA, Canada |
| 585 | 14K | 58.3% | USA, Norway |
| 750 | 18K | 75.0% | Europe, fine jewelry |
| 833 | 20K | 83.3% | Middle East |
| 916 | 22K | 91.6% | India, Middle East |
| 999 | 24K | 100.0% | Bullion, investment |
How to Check Gold Purity at Home
1. Look for Hallmark Stamps
The most reliable method is checking the hallmark stamp inside rings (inside the band), on necklace clasps, or on bracelet clasps. Use a jeweler's loupe or magnifying glass to read tiny stamps like "750", "585", or "375".
Common stamp locations:
- • Rings: Inside the band
- • Necklaces: Near the clasp
- • Bracelets: Inside clasp or end links
- • Earrings: On the posts or backs
2. Magnet Test
Real gold is not magnetic. Hold a strong magnet near your gold piece — if it's attracted, it's either fake or gold-plated. However, some alloy metals (nickel, iron) in white gold may show slight attraction, so this test isn't 100% conclusive.
⚠️ Important note:
This test can't distinguish between different karat grades. It only helps identify completely fake pieces.
3. Float Test (Density)
Pure 24K gold has a density of 19.3 g/cm³. Fill a graduated cylinder with water, record the volume, drop in your gold piece, and measure again. Divide weight by volume change to get density. 18K gold is around 15-16 g/cm³, 14K around 13-14 g/cm³.
Formula: Density = Weight (g) ÷ Volume displaced (mL)
4. Professional Testing
For accurate karat verification, jewelers use acid tests or electronic gold testers. Acid testing applies nitric acid — fake gold dissolves, real gold doesn't. XRF spectrometers can determine exact gold percentage non-destructively.
💡 Tip: Most jewelry stores offer free testing if you're considering a purchase.
Common Gold Alloy Compositions
Pure 24K gold is too soft for jewelry. By mixing it with other metals (alloys), jewelers create durable pieces in different colors. The exact recipe determines the final color and properties.
Yellow Gold Alloys
18K Yellow Gold (75% gold)
- • 75% Pure gold
- • 12.5% Silver
- • 12.5% Copper
Rich yellow color, popular in Europe
14K Yellow Gold (58.5% gold)
- • 58.5% Pure gold
- • 20% Silver
- • 21.5% Copper
Most popular in USA, very durable
White Gold Alloys
18K White Gold (Palladium-based)
- • 75% Pure gold
- • 15% Palladium
- • 10% Silver
Naturally white, no plating needed
18K White Gold (Nickel-based)
- • 75% Pure gold
- • 12.5% Nickel
- • 12.5% Copper
Cheaper but can cause allergic reactions
Rose Gold Alloys
18K Rose Gold
- • 75% Pure gold
- • 20-22% Copper
- • 3-5% Silver
Romantic pinkish hue from high copper content
14K Red Gold
- • 58.5% Pure gold
- • 35% Copper
- • 6.5% Silver
Deep reddish tone, very durable
Caring for Different Karat Gold
Each karat grade requires slightly different care. Higher karat gold is softer and scratches more easily, while lower karat gold can tarnish due to alloy metals.
High Karat (22K-24K)
- ✓ Remove before physical activities — very soft and prone to dents
- ✓ Store separately in soft cloth pouches to prevent scratching
- ✓ Clean with warm water and mild soap only — avoid abrasive cleaners
- ✓ 24K doesn't tarnish, but 22K may discolor slightly over decades
Medium Karat (14K-18K)
- ✓ Perfect for everyday wear — durable enough for daily activities
- ✓ Remove before swimming (chlorine can damage alloys)
- ✓ Clean monthly with jewelry cleaner or warm soapy water
- ✓ Professional polishing every 1-2 years restores shine
Low Karat (8K-10K)
- ✓ Extremely durable — ideal for work jewelry and active lifestyles
- ✓ May tarnish faster due to higher alloy content — clean regularly
- ✓ Avoid perfumes and lotions (can react with copper/silver alloys)
- ✓ Polish with soft cloth to remove tarnish and restore brightness
Universal Gold Care Tips
- • Remove jewelry before showering (soap residue dulls shine)
- • Put on jewelry last — after makeup, perfume, and hairspray
- • Store in a cool, dry place away from sunlight
- • Avoid harsh chemicals (bleach, chlorine, ammonia)
- • Get prongs checked annually for loose stones
- • Use ultrasonic cleaners only for solid gold (not hollow pieces)
Frequently Asked Questions
What is the difference between 24K, 18K, and 14K gold?
24K gold is pure gold (99.9%). 18K gold is 75% gold mixed with 25% other metals like silver or copper. 14K gold is 58.5% gold. Higher karats are purer and more yellow; lower karats are harder and more affordable.
What does the karat number on gold jewellery mean?
The karat number indicates how many parts out of 24 are pure gold. 18K means 18 out of 24 parts are gold (75% purity). The hallmark stamped on jewellery (e.g. 750 for 18K, 585 for 14K) shows the parts-per-thousand purity.
Which gold karat is best for everyday jewellery?
14K (58.5% gold) is the most popular choice for everyday jewellery in the US — it balances durability and gold content. 18K is preferred in Europe and Asia for its richer colour. 24K is too soft for most jewellery.
Is higher karat gold always more valuable?
Higher karat gold contains more pure gold, so the raw material is worth more. However, 24K jewellery is rarely sold because it scratches easily. The value of a piece also depends on craftsmanship, weight, and design.
Can I shower with my gold jewelry?
While gold won't rust or corrode, showering with gold jewelry isn't recommended. Soap, shampoo, and conditioner leave residue that dulls the shine over time. Additionally, slippery hands increase the risk of dropping and losing pieces down the drain.
Why does my 14K gold ring turn my finger green?
The green discoloration comes from copper in the gold alloy reacting with your skin's acidity, sweat, or lotions. This is completely harmless and more common with lower karat gold (which has more copper). To prevent it, remove rings before washing hands, apply clear nail polish to the inside of the band, or choose higher karat gold.
Sources
Karat numbers apply equally to all gold colors. Once you know the purity, explore how different alloys change the appearance — same percentage, completely different look.