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Triclinic Crystal Triclinic Crystal
Apatite Crystals Apatite Crystals
Hexagonal Crystal Hexagonal Crystal

Apatite Crystals

Apatite Crystals
Apatite includes a number of calcium phosphate minerals, including calcium phosphate fluoride, the material of teeth and bones. These yellow apatite crystals belong to the hexagonal crystal system, which means they have one axis of symmetry in the elongated direction of the crystal and three other symmetrical axes in a plane at right angles to the first. A cross-sectional slice of an apatite crystal would produce a hexagon.
George Whiteley/Photo Researchers, Inc.
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Apatite; Crystal (mineral)
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