Jewelry & Precious Metals Converter - Free Online Tool

Free online jewelry & precious metals unit converter with 11+ supported units and conversion table.

💍 Jewelry & Precious Metals Converter

Select your units from the lists below

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From Unit

24 Karat Gold
Symbol: 24k

18 Karat Gold
Symbol: 18k

14 Karat Gold
Symbol: 14k

10 Karat Gold
Symbol: 10k

Percent Purity
Symbol: %

Diamond Karat
Symbol: ct

Milligram
Symbol: mg

Troy Ounce
Symbol: oz t

Gram
Symbol: g

Pennyweight
Symbol: dwt

Grain
Symbol: gr

To Unit

24 Karat Gold
Symbol: 24k

18 Karat Gold
Symbol: 18k

14 Karat Gold
Symbol: 14k

10 Karat Gold
Symbol: 10k

Percent Purity
Symbol: %

Diamond Karat
Symbol: ct

Milligram
Symbol: mg

Troy Ounce
Symbol: oz t

Gram
Symbol: g

Pennyweight
Symbol: dwt

Grain
Symbol: gr

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💍 Jewelry & Precious Metals Converter

Jewelry measurements appear in gold purity, gemstone weight, and jewelry valuation. Convert between karats (gold purity), carats (gemstone weight), troy ounces, grams, pennyweights, and other jewelry units instantly. Whether you're buying jewelry, appraising pieces, or working in jewelry manufacturing, our converter handles the calculations.

💍 About Jewelry & Precious Metals

Jewelry measurement uses specialized units for precious metals and gemstones. Karat (K) measures gold purity on a 24-part scale, with 24K being pure gold. Carat (ct) measures gemstone weight, with one carat equaling 0.2 grams. Troy ounces and pennyweights are traditional units for precious metal weight. Jewelry measurement is fundamental to jewelry manufacturing, valuation, and consumer protection. The ability to accurately measure and convert between different jewelry units is crucial for understanding jewelry value and quality. Gold purity affects both value and durability, while gemstone carat weight determines size and price. Understanding these units and converting between them is essential for jewelry purchasing, appraisals, and international jewelry standards compliance.

Understanding Jewelry & Precious Metals Measurement

Jewelry measurement encompasses two distinct uses of similar-sounding terms. Karat (K) measures gold purity, expressing the proportion of pure gold in an alloy out of 24 parts. For example, 18K gold contains 18 parts gold and 6 parts other metals, equaling 75% pure gold. Carat (ct) measures gemstone weight, with one metric carat equaling exactly 0.2 grams (200 milligrams). Precious metal weight uses the troy system: one troy ounce equals approximately 31.103 grams, while one pennyweight equals 1/20 of a troy ounce. The metric carat was standardized in 1907 as exactly 0.2 grams, replacing various regional carat weights that ranged from about 0.197 to 0.205 grams. These standardized measurements ensure consistency in jewelry valuation and manufacturing worldwide.

📜 History & Context

The history of jewelry measurement dates back to ancient times, when traders used carob seeds as counterweights for gemstones. The word "carat" comes from the Arabic "qīrāṭ," derived from Greek "kerátion" meaning "little horn" or "seed." These seeds were believed to be uniform, making them useful as weight standards, though actual carat weights varied by region until standardization. The karat system for gold purity has medieval European origins, based on dividing coins into 24 parts. Pure gold was considered 24 karat, while alloys used lower karat values. Hallmarking systems developed to protect consumers, with England requiring gold and silver marks since 1300. The metric carat was standardized internationally in 1907 at exactly 0.2 grams, replacing regional variations. Modern hallmarking laws, such as the UK's Hallmarking Act of 1973, continue to regulate gold purity standards and consumer protection.

✨ Fun Facts

• The word "carat" comes from carob seeds, which ancient traders used as counterweights because they were believed to be uniform—though actual carat weights varied by region until standardized in 1907.
• The metric carat was standardized in 1907 as exactly 0.2 grams (200 milligrams), replacing regional variations that ranged from about 0.197 to 0.205 grams.
• Gold karat measures purity out of 24 parts: 24K is pure gold, 18K is 75% gold, 14K is about 58.3% gold, and 10K is about 41.7% gold.
• One carat is divided into 100 points, so a 0.75-carat diamond equals 75 points, allowing precise measurement of small gemstones.
• England's hallmarking system dates to 1300, when King Edward I decreed that all gold and silver wares should be marked with the leopard's head to certify purity.

💡 Real-World Examples

• Jewelry purchasing: Buying gold jewelry requires understanding karat purity. Converting between karats and percentage purity helps with value assessment and quality comparison.
• Gemstone valuation: Gemstone appraisals measure weight in carats. Converting to grams or other units helps with valuation and international jewelry standards.
• Jewelry manufacturing: Jewelers work with precious metals measured in troy ounces or grams. Converting between units helps with material calculations and international manufacturing standards.
• Jewelry appraisals: Professional appraisals measure gold purity and gemstone weight in various units. Converting between units helps with accurate valuation and international appraisal standards.
• Jewelry design: Jewelry designers specify gemstone sizes in carats or millimeters. Converting between units helps with design planning and manufacturing specifications.
• Precious metal trading: Gold and silver trading measure weight in troy ounces. Converting to grams or other units helps with international precious metal markets.
• Jewelry repair: Jewelry repair work measures materials in various units. Converting between units helps with material ordering and repair specifications.
• Consumer education: Understanding jewelry requires knowledge of karat and carat measurements. Converting between units helps with consumer education and informed purchasing decisions.

🔧 Common Applications

• Jewelry manufacturing and design: Jewelry production measures gold purity in karats and gemstone weight in carats. Converting between units helps with manufacturing specifications and international jewelry standards.
• Jewelry valuation and appraisals: Professional appraisals measure gold purity and gemstone weight in various units. Converting between units helps with accurate valuation and international appraisal standards.
• Jewelry retail and consumer education: Jewelry sales and consumer information use karat and carat measurements. Converting between units helps with consumer understanding and informed purchasing decisions.
• Precious metal trading: Gold and silver trading measure weight in troy ounces or grams. Converting between units helps with international precious metal markets and trading standards.
• Jewelry repair and restoration: Jewelry repair work measures materials in various units. Converting between units helps with material ordering, repair specifications, and restoration standards.

❓ Frequently Asked Questions

+ What is the difference between karat and carat?

Karat (kt or k) measures gold purity: 24 karat is pure gold, 18 karat is 75% gold, 14 karat is 58.3% gold. Carat (ct) measures gemstone weight: 1 carat equals 200 milligrams or 0.2 grams. These are different units despite similar spelling.

+ How do I convert carats to grams?

To convert carats (ct) to grams, multiply the carat value by 0.2. For example, 1 carat equals 0.2 grams, 5 carats equals 1 gram, and 10 carats equals 2 grams. Carats measure gemstone weight.

+ How do I convert troy ounces to grams?

To convert troy ounces to grams, multiply the troy ounce value by 31.1035. For example, 1 troy ounce equals approximately 31.1 grams, and 10 troy ounces equals approximately 311 grams. Troy ounces are used for precious metals.

+ What does 18 karat gold mean?

18 karat gold means the alloy is 18 parts gold out of 24 total parts, or 75% pure gold. The remaining 25% is other metals (usually copper, silver, or zinc) added for strength and color. Higher karat means more pure gold.

+ How do I convert grams to carats?

To convert grams to carats, multiply the gram value by 5. For example, 1 gram equals 5 carats, 0.5 grams equals 2.5 carats, and 2 grams equals 10 carats. This conversion is used for gemstone weight measurements.