Convert Troy Ounces to Carats
Convert Troy Ounces (ozt) to Carats (ct) instantly and accurately.
Conversion Formula
ct = ozt × 155.517384
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).
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.
Quick Reference Table
| Troy Ounces (ozt) | Carats (ct) |
|---|---|
| 1 ozt | 155.517 ct |
| 2 ozt | 311.035 ct |
| 5 ozt | 777.587 ct |
| 10 ozt | 1555.17 ct |
| 25 ozt | 3887.93 ct |
| 50 ozt | 7775.87 ct |
| 100 ozt | 15551.7 ct |