Recently I had the privilege to attend Converge—a unique event uniting GIA’s research and education with our sister organization the American Gem Society’s professional development opportunities—and ...
Dumortierite is an orthorhombic, fibrous aluminum borosilicate mineral (Al 7 BO 3 (SiO 4) 3 O 3) that typically forms slender prismatic crystals with spectacular color and pleochroism. The crystals ...
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