I knew the difference between karats and carrots, but I did know there was a difference between karats and carats.
1 a unit of weight for precious stones and pearls, now equivalent to 200 milligrams : a half-carat diamond ring.
2 chiefly British spelling of karat .
ORIGIN late Middle English (sense 2) : from French, from Italian carato, from Arabic ḳīrāṭ (a unit of weight), from Greek keration ‘fruit of the carob’ (also denoting a unit of weight), diminutive of keras ‘horn,’ with reference to the elongated seedpod of the carob.
karat |ˈkarət| ( chiefly Brit. also carat)
a measure of the purity of gold, pure gold being 24 karats : an ounce of 24-karat gold.