Diamond & Diamond Grading Exam Questions and Answers | Latest Version | 2025/2026 | Correct & Verified

Diamond & Diamond Grading Exam Questions and Answers | Latest Version | 2025/2026 | Correct & Verified What is the hardest naturally occurring mineral on Earth? Diamond Which characteristic determines a diamond’s clarity grade? The number, size, position, and visibility of internal and external flaws What does the term “carat” measure in a diamond? Weight Which diamond color is considered the most rare and valuable? Colorless (D grade) What is the process called when a diamond is cut to enhance its brilliance? Faceting Which tool is used to examine inclusions in a diamond? Loupe What does the “cut” of a diamond affect most? 2 Brilliance and fire Which clarity grade indicates a diamond with no visible inclusions under 10x magnification? Flawless (FL) What is a “fire” in a diamond? The dispersion of light into spectral colors Which term describes tiny internal fractures within a diamond? Feathers What type of diamond exhibits a play of colors when rotated under light? Opalescent or multi-colored diamonds (though true diamonds show fire, not opalescence) Which shape of diamond maximizes carat weight while minimizing visible inclusions? Cushion cut What is the significance of a diamond’s fluorescence? It affects appearance under UV light and sometimes value Which diamond grading system is most widely recognized worldwide? GIA (Gemological Institute of America) 3 What does the term “table” refer to in a diamond? The large, flat top facet Which cut is most popular for engagement rings? Round brilliant cut What is an “inclusion” in a diamond? Any internal characteristic or imperfection Which facet arrangement produces the most brilliance in a round diamond? Standard brilliant cut with 57 or 58 facets What does “girdle” mean in diamond terminology? The outer edge separating the crown from the pavilion Which clarity grade indicates minor inclusions visible under 10x magnification but not to the naked eye? VS1 or VS2 What is the effect of a diamond’s cut proportion on light performance? Determines brightness, fire, and scintillation 4 Which term refers to the lower portion of a diamond beneath the girdle? Pavilion What is a “culet” in a diamond? The small facet at the bottom tip of a diamond Which diamond color grade is considered near colorless? G-H What tool measures a diamond’s refractive index? Refractometer What does a “hearts and arrows” pattern indicate? Precision in cut symmetry for round brilliant diamonds Which part of a diamond affects its sparkle the most? Cut and facet angles What is the most common flaw found in natural diamonds? Internal inclusions like crystals or feathers 5 Which process can enhance a diamond’s color or clarity? Laser drilling, HPHT treatment, or irradiation Which factor has the least impact on a diamond’s value? Shape preference compared to cut, clarity, color, and carat What does “excellent cut” indicate in a