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Activity

2022

• COLOR ORIGIN OF COLOR CHANGE SAPPHIRE
  T225 Gemological Research in the Twenty-First Century—Gem Minerals and Localities
  Wednesday, 12 October 2022

  8:00 AM - 12:00 PM

  503

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2021

• HOW TO CALCULATE COLOR FROM SPECTRA OF UNIAXIAL GEMSTONES
  T107 Gemological Research in the 21st Century—Gem Minerals and Localities
  Monday, 11 October 2021

  1:30 PM - 5:30 PM

  A107–A109