What are the three common categories of defects in diamonds?

• A. Point, Line, and Volume
• B. Point, Area, and Volume
• C. Point, Line, and Plane
• D. Line, Volume, and Grain Boundary

Answer: (A)

Defects are classified by their dimensional extent, which is why three common categories are recognized: point defects (0D) such as vacancies or impurity atoms, line defects (1D) like dislocations that thread through the crystal, and volume defects (3D) such as inclusions and internal cavities that occupy space inside the diamond. This dimensional framework helps explain how defects affect appearance and integrity: point defects are typically too small to see, line defects can disrupt light paths and lattice continuity, and volume defects can significantly affect transparency and strength. While planar features and grain boundaries exist, the three-category approach most often used in practice exams emphasizes these 0D, 1D, and 3D defects.