#precious_stone__jewel__gem  a precious or semiprecious stone incorporated into a piece of jewelry
  supertype:  jewelry__jewellery  an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)
  subtype:  solitaire.precious_stone  a gem (usually a diamond) in a setting by itself
  subtype:  diamond  a transparent piece of diamond that has been cut and polished and is valued as a precious gem
     subtype:  ice.diamond  (informal) diamonds; "look at the ice on that dame!"
  subtype:  ruby  a transparent piece of ruby that has been cut and polished and is valued as a precious gem
  subtype:  pearl  a smooth lustrous round structure inside the shell of a clam or oyster; much valued as a jewel
     subtype:  seed_pearl  a small imperfect pearl
  subtype:  emerald.precious_stone  a transparent piece of emerald that has been cut and polished and is valued as a precious gem
  subtype:  sapphire  a transparent piece of sapphire that has been cut and polished and is valued as a precious gem

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