Convert Kilogram (kg) to Ton (Assay) (UK) (AT (UK)) instantly.
About these units
Kilogram (kg)
The kilogram is the base unit of mass in the SI system and the only SI unit defined directly by a fundamental constant rather than a physical object. Originally, its definition was tied to a platinum–iridium artifact stored in France—the famous "International Prototype Kilogram." Over time, tiny mass changes in the prototype and its official copies created difficulties for high-precision science. In 2019, the kilogram was redefined using Planck's constant, linking mass to the laws of quantum physics through the Kibble balance. This innovation ensures universality, stability, and reproducibility across the world. The kilogram is central to commerce, science, engineering, and every quantitative field dealing with matter. Its decimal relationships with other metric units (grams, milligrams, tons) make it universally convenient. From groceries to spacecraft mass budgets, the kilogram anchors modern mass measurement.
Ton (Assay) (UK) (AT (UK))
The UK assay ton, slightly different from the US version, is defined as 32.666 grams. Like its American counterpart, it was designed so that milligram-level assay results could be easily interpreted as ounces of metal per ton of ore. In British mining operations of the 19th and early 20th centuries, the UK assay ton streamlined economic decision-making by directly correlating lab-scale measurements with bulk extraction expectations. Although now historical, its existence illustrates how different countries tailored their measurement systems to local mining economics and metal markets.