A carrot is an orange vegetable and has nothing to do with jewelry - it’s a favorite with rabbits. But if you are talking about carats, then you are talking about the weight of gems. A carat is 1/5 a gram and there are 28.3 grams in an ounce or 141.5 carats in an ounce. When you see CT after a number it’s referring to the weight of the gem. To make thing more confusing we have calibrated sizes, and for the different calibrations have been issued a carat weight based of the weight of a diamond. So a calibrated stone will be a little less than it stated weigh. (A calibrated stone will fit into a setting, were one that’s not wont.)
And with Carrots we also have Karat, which is the purity of Gold, and is written as kt. A 24kt gold item is pure Gold. A 14kt ring would be 58.3% Pure, which is the most popular in Gold Jewelry in the US. In Europe 18kt is most popular and is 75% pure. And 10kt is 41.6% pure. Because of the high cost of Gold 10kt is becoming much more popular.