Convert Stone (US) (st (US)) to Microgram (µg) instantly.
About these units
Stone (US) (st (US))
The US stone was an informal and nonstandardized unit occasionally used in the 19th century, with no single agreed-upon value. Unlike the British stone (14 pounds), the US stone varied regionally and by trade context, typically ranging from 12 to 16 pounds, depending on the commodity and location. Farmers, butchers, and merchants sometimes used stones to weigh produce, meat, or livestock, but the lack of uniform regulation prevented it from becoming an official or widely adopted unit. Today, the US stone is entirely obsolete, but references to it appear in historical American trade documents, agricultural records, and pre-standardization weight systems. It serves as a reminder of the diversity of early American measurements before the widespread adoption of the avoirdupois pound.
Microgram (µg)
A microgram is one-millionth of a gram, essential in pharmacology, nutrition science, and chemical analysis. Many vitamins, especially fat-soluble ones like vitamin D and K, are prescribed or measured in micrograms, as exceeding recommended doses can be harmful. In environmental monitoring, pollutant levels—such as airborne particulate matter—are often expressed in micrograms per cubic meter. Researchers working with catalysts or rare biological compounds rely on microgram-scale measurements for precise experiments. The microgram is indispensable in fields requiring tight control over small masses that impact biological or chemical systems significantly.