carats

noun
  1. 1

    A unit of weight for precious stones and pearls, equivalent to 200 milligrams.

  2. 2

    Any of several units of weight, varying from 189 to 212 mg, the weight of a carob seed.

  3. 3

    A measure of the purity of gold, pure gold being 24 carats.

Source: https://en.wiktionary.org/wiki/carat, https://en.wiktionary.org/wiki/carats