Convert Carat to Stone (UK)

The carat originated from the use of the carob seed (from the Ceratonia siliqua tree) as a reference for weight in ancient times. These seeds were used because of their relatively consistent weight, and they were widely available across regions. The term "carat" comes from the Greek word "keration", which means "little horn," referring to the carob seed. Over time, the carat became standardized, and in 1907, the International Union of Pure and Applied Chemistry (IUPAC) defined the carat as 200 milligrams, ensuring consistency in the measurement of gemstones worldwide.

The stone has ancient origins, dating back to the medieval period. Historically, the weight of a stone varied depending on the commodity being measured, ranging from 5 to 30 pounds. For example, in England, the stone was used to measure wool, and different types of goods had their own stone weights. In 1300, a standardized 14-pound stone was adopted for use in the wool trade. Over time, this 14-pound definition became the standard, and the stone was widely used in the UK for measuring body weight, a tradition that continues today.