Convert Scruples to Carats
Convert Scruples (s ap) to Carats (ct) instantly and accurately.
Conversion Formula
ct = s ap × 6.479891
About Scruples
A scruple (s ap) is a unit of the apothecary weight system equal to 20 grains or approximately 1.296 grams. Derived from the Latin 'scrupulus' (a small sharp stone used as a counterweight), it was the basic dispensing unit in pre-metric pharmacy across Europe. The apothecary system divided the fluid ounce into 8 drams, each dram into 3 scruples, and each scruple into 20 grains - a hierarchy memorised by every 19th-century pharmacist.
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
| Scruples (s ap) | Carats (ct) |
|---|---|
| 1 s ap | 6.47989 ct |
| 2 s ap | 12.9598 ct |
| 5 s ap | 32.3995 ct |
| 10 s ap | 64.7989 ct |
| 25 s ap | 161.997 ct |
| 50 s ap | 323.995 ct |
| 100 s ap | 647.989 ct |