Assertion: kilogram | /r/HasProperty | replaced by new definition of the kilogram
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Source sentences:
text: The International Prototype of the Kilogram (referred to by metrologists as the IPK; sometimes called the ur-kilogram, or urkilogram, particularly by German-language authors writing in English:30:64) is an object that was used to define the magnitude of the mass of the kilogram from 1889, when it replaced the Kilogramme des Archives, until 2019, when it was replaced by a new definition of the kilogram based on physical constants.