Translucent cross section of a tourmaline crystal. Tourmaline is a boron-silicate mineral, crystal system trigonal, and commonly forming crystals with

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Translucent cross section of a tourmaline crystal. Tourmaline is a boron-silicate mineral, crystal system trigonal, and commonly forming crystals with an elongate prismatic habitat. It occurs in a number of colors, some of which are much sought after as semi-precious gemstones. This section illustrates the interior structure of the crystal, complete with the tri-axial cross and the six-sided circumference typical for the trigonal crystal symmetry. Actual diameter 80 mm

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Size: 5416px × 6454px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: axial, boron, color, cross, cross-section, crystal, crystalline, elongate, gemstone, mineral, mineralogy, multicolored, silicate, symmetry, tourmaline, translucent, tri-axial, turmaline