4Cs of Diamond Quality Flashcards

Two diamonds are each 0.50 carats but have different diameters. What most likely accounts for this difference?

Answer: Different cut proportions

A shallower-cut diamond spreads weight across a wider diameter, while a deeper stone concentrates weight below the girdle.

Which of the following best describes a diamond graded 'VS1' by GIA?

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.

A 'feather' in diamond clarity grading refers to:

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.

On the GIA color grading scale, which letter grade represents the most colorless diamond possible?

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.

What is 'scintillation' as defined by GIA in evaluating cut quality?

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.

A jeweler tells a customer that a diamond weighs '150 points.' How many carats is this diamond?

Answer: 1.5 carats

One carat equals 100 points, so 150 points equals 1.50 carats.

Which cut grade does GIA assign only to round brilliant cut diamonds, NOT to fancy shaped diamonds?

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.