#gemstone__gem__stone  a crystalline rock that can be cut and polished for jewelry
  supertype:  crystal  a solid formed by the solidification of a chemical and having a highly regular atomic structure
  subtype:  cabochon  opaque_gem  transparent_gem
  part of:  jewelry__jewellery  an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)

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