Convert Carats to Troy Ounces

Convert Carats (ct) to Troy Ounces (ozt) instantly and accurately.

Carats (ct)
Troy Ounces (ozt)

Conversion Formula

ozt = ct × 0.006430149314

About Carats

A metric carat (ct or CD) is exactly 200 milligrams (0.2 g), the universal standard for weighing gemstones. Established internationally in 1907, it replaced fractionally different regional carat weights previously used in different countries. The total weight of a diamond or colored gemstone is always expressed in carats: a 1.00 ct diamond of excellent cut and color can command over $5,000. The Cullinan diamond, the largest gem-quality rough diamond ever found, weighed 3,106.75 carats.

About Troy Ounces

The troy ounce (ozt or oz t) is the global standard for weighing and pricing precious metals - gold, silver, platinum, and palladium. Equal to 31.1034768 grams (about 10% heavier than the avoirdupois ounce), it originates from the medieval fair at Troyes, France, where a standardised weight system facilitated international trade. All gold spot prices quoted on financial markets (LBMA, COMEX, MCX) are priced per troy ounce. A standard 'Good Delivery' gold bar approved by the London Bullion Market Association weighs approximately 400 troy ounces (12.4 kg).

Quick Reference Table

Carats (ct)Troy Ounces (ozt)
1 ct0.00643015 ozt
2 ct0.0128603 ozt
5 ct0.0321507 ozt
10 ct0.0643015 ozt
25 ct0.160754 ozt
50 ct0.321507 ozt
100 ct0.643015 ozt

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