Convert Carat to Kilogram

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 kilogram originated during the French Revolution in the late 18th century as part of the metric system's development. Initially, it was defined as the mass of one cubic decimeter of pure water at 4°C, chosen for its universal availability and consistency. In 1799, a physical standard called the Kilogram of the Archives, a platinum cylinder, was created to represent the unit. Later, in 1889, the International Prototype of the Kilogram (IPK), a more precise platinum-iridium cylinder, was adopted as the global standard, stored in France with copies distributed worldwide.

Over time, physical changes in the IPK led to inconsistencies, prompting scientists to redefine the kilogram. In 2019, it was redefined based on the Planck constant (h), a fundamental constant of nature, linking the kilogram to unchanging physical properties rather than a physical object. This modern definition ensures long-term precision and stability for the unit of mass.