GIA 4Cs of Diamond Quality 3 — Questions and Answers
Question 1: Two diamonds are each 0.50 carats but have different diameters. What most likely accounts for this difference?
- Different fluorescence levels
- Different cut proportions (Correct answer)
- Different color grades
- Different clarity grades
Correct answer: Different cut proportions
A shallower-cut diamond spreads weight across a wider diameter, while a deeper stone concentrates weight below the girdle.
Question 2: Which of the following best describes a diamond graded 'VS1' by GIA?
- Inclusions visible to the naked eye
- Minor inclusions difficult to see under 10x magnification (Correct answer)
- Very minor inclusions easily seen under 10x magnification
- Inclusions somewhat easy to see under 10x magnification
Correct answer: Minor inclusions difficult to see under 10x magnification
VS1 (Very Slightly Included 1) describes diamonds where inclusions are minor and difficult to see even under 10x magnification.
Question 3: A 'feather' in diamond clarity grading refers to:
- A white surface scratch
- A small fracture or crack within the diamond (Correct answer)
- A needle-like crystal inclusion
- A cloud of tiny pinpoints
Correct answer: A small fracture or crack within the diamond
A feather is a fracture inside the diamond that, when viewed at certain angles, resembles a feathery pattern.
Question 4: On the GIA color grading scale, which letter grade represents the most colorless diamond possible?
- A
- C
- D (Correct answer)
- Z
Correct answer: D
GIA's color scale begins at D (most colorless) and extends to Z (light yellow or brown), intentionally avoiding A-C to prevent confusion with older systems.
Question 5: What is 'scintillation' as defined by GIA in evaluating cut quality?
- The total amount of white light reflected from a diamond
- The dispersion of light into spectral colors
- The pattern of light and dark areas plus the flashes of light when a diamond moves (Correct answer)
- The brightness visible from the table facet only
Correct answer: The pattern of light and dark areas plus the flashes of light when a diamond moves
Scintillation encompasses both the sparkle (flashes of light) and the pattern of light and dark areas created as the diamond, observer, or light source moves.
Question 6: A jeweler tells a customer that a diamond weighs '150 points.' How many carats is this diamond?
- 0.15 carats
- 1.5 carats (Correct answer)
- 15 carats
- 150 carats
Correct answer: 1.5 carats
One carat equals 100 points, so 150 points equals 1.50 carats.
Question 7: Which cut grade does GIA assign only to round brilliant cut diamonds, NOT to fancy shaped diamonds?
- Polish grade
- Symmetry grade
- Overall cut grade (Correct answer)
- Fluorescence grade
Correct answer: Overall cut grade
GIA issues an overall cut grade only for standard round brilliant diamonds; fancy shapes receive polish and symmetry grades but not a comprehensive cut grade.
GIA 4Cs of Diamond Quality 3
Two diamonds are each 0.50 carats but have different diameters.
What most likely accounts for this difference?