How to evaluate cut stones — proportion, symmetry, polish, and color
Track: Gemology · Duration: 36 min
Video lesson
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Course reader
How to evaluate cut stones — proportion, symmetry, polish, and color
Gemology workbook — ID, cutting, evaluation, setting, and birthstones next to the video.
Make vs shape
- Proportion: crown vs pavilion angles influence brilliance and face-up size.
- Symmetry: misaligned facets, wavy girdle, off-center culet.
- Polish: drag lines, pitting, burned facets.
Colored stones
- Watch for windowing (see-through patch), extinction (dark patches), and pleochroic orientation for best face-up hue.
- Value ties to color, clarity, cut quality, carat, rarity — not identical to diamond “4Cs” weighting.
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Lesson quiz
Each attempt uses a random set of questions with shuffled answer choices. Pass at 70% or higher to mark the lesson complete.