Assertion: prototype kilogram | /r/HasProperty | a platinum alloy cylinder
Facets:
Source sentences:
text: Following a historic vote on Friday at the General Conference on Weights and Measures, in Versailles, the kilogram will no longer be defined by the international prototype kilogram (IPK), a platinum alloy cylinder fashioned in 1889, but by Planck’s constant, a number that is deeply rooted in the quantum world.