Convert Atomic Mass Unit (u) to Ton (Assay) (US) (AT (US)) instantly.
About these units
Atomic Mass Unit (u)
The atomic mass unit (u) is defined as exactly 1/12 the mass of a neutral carbon-12 atom, which makes it approximately 1.66053906660 × 10⁻²⁷ kilograms. This definition allows scientists to express atomic and molecular masses in a convenient, intuitive scale that aligns with the structure of the periodic table. By anchoring the unit to carbon-12, chemists and physicists gained a universal reference point that harmonizes molecular weight, relative isotopic abundance, and mass spectroscopy results. The atomic mass unit effectively normalizes the complexity of atomic masses into whole-number or near-whole-number values for most nuclei. In chemistry, u is indispensable for calculating molar masses, reaction stoichiometry, and isotopic compositions. It is also used across nuclear physics, astrophysics, and biophysics, demonstrating the universality of atomic-scale measurement.
Ton (Assay) (US) (AT (US))
The US assay ton is a specialized unit used in mining and metallurgy for evaluating ore grades. It is defined as 29.166⅔ grams, a very small mass chosen to simplify calculations relating assay results to tons of ore. The idea is that if an assay ton of sample yields 1 milligram of precious metal, then one actual ton of ore contains 1 ounce of that metal. This scaling makes laboratory results directly translatable to mining yields. While obsolete in modern industrial practice, where metric units dominate, the assay ton remains important in historical mining records and for researchers studying early industrial metallurgy.