tanzanite

Noun

tanzanite (countable and uncountable, plural tanzanites)

1. A trichroic violet-blue variety of the mineral zoisite mined in Tanzania, used as a gemstone.
   • For those to whom gems light the way, a brand new semi-precious stone will be seen for the first time. Called "Tanzanite," the stone was discovered recently in Tanzania. A blue, very much like sapphire, with a slight violet cast, it is exclusive with Tiffany.1968 October 1, Margene Morris, “Tiffany gets a new home”, in San Francisco Examiner, number 80, San Francisco, Calif.: San Francisco Newspaper Print Co., →ISSN, →OCLC, page 22, column 2
   • Last February the new gem was spotted by Harry Platt. […] Just what happened to zoisite in one certain mine in Tanzania, near the Kenya border, nobody knows. Harry Platt bought as many of the freak stones as he could find and had them cut and polished especially for Tiffany. He named the stone...1968 October 3, Eugenia Sheppard, “Inside Fashion: Something new at Tiffany’s is Tanzanian blue gem”, in Durham Morning Herald, final edition, Durham, N.C.: The Durham Herald Co., →OCLC, section B...

   Synonyms:

   blue zoisite, pleochroic zoisite, vanadium zoisite