CDG Diamond Pricing & Valuation 1 — Questions and Answers
Question 1: What is the primary purpose of the Rapaport Diamond Report (Rap Sheet)?
- To certify the authenticity of individual diamonds
- To provide a standardized wholesale price benchmark for round brilliant diamonds by size and grade (Correct answer)
- To document a diamond's chain of custody from mine to market
- To list retail prices for finished jewelry pieces containing diamonds
Correct answer: To provide a standardized wholesale price benchmark for round brilliant diamonds by size and grade
The Rapaport Diamond Report is a widely used weekly price list that serves as a benchmark for wholesale diamond prices organized by carat weight, color, and clarity grade.
Question 2: Among the 4Cs, which factor typically has the greatest influence on a diamond's per-carat price at higher quality levels?
- Cut grade
- Clarity grade
- Color grade (Correct answer)
- Carat weight
Correct answer: Color grade
At higher quality tiers, color grade tends to have the most dramatic impact on per-carat price because D–F colorless diamonds command significant premiums over near-colorless grades.
Question 3: How does strong blue fluorescence typically affect the price of a D–F color, high-clarity diamond?
- It increases the price by 5–15% due to enhanced visual appeal
- It has no measurable effect on price for top-color diamonds
- It decreases the price because it can cause a hazy or oily appearance in some stones (Correct answer)
- It increases the price only for stones graded VS2 or better
Correct answer: It decreases the price because it can cause a hazy or oily appearance in some stones
Strong blue fluorescence in D–F color diamonds is generally considered a negative factor because it can produce a hazy or milky appearance, reducing the stone's value.
Question 4: In diamond trading, what does the term 'off-make' refer to?
- A diamond that has been treated to improve its color
- A diamond with proportions that deviate significantly from ideal cutting standards (Correct answer)
- A diamond whose grading report has been issued by a non-recognized laboratory
- A diamond that has been re-cut from a larger rough stone
Correct answer: A diamond with proportions that deviate significantly from ideal cutting standards
An 'off-make' diamond has proportions outside accepted cutting standards—such as excessive depth or poor symmetry—resulting in a discount from Rapaport prices.
Question 5: What pricing phenomenon occurs at 'magic sizes' such as 0.50 ct, 1.00 ct, and 2.00 ct?
- Diamonds at these weights are automatically assigned a higher clarity grade
- Diamonds just below these weights sell at a discount, while diamonds at or above them command a premium (Correct answer)
- These weights correspond to minimum size requirements for GIA grading reports
- Diamonds at these weights qualify for free laser inscription
Correct answer: Diamonds just below these weights sell at a discount, while diamonds at or above them command a premium
Diamonds at or just above 'magic sizes' command higher per-carat prices due to strong consumer demand for milestone weights, while stones just below are often discounted.
Question 6: Why does the per-carat price of diamonds generally increase as carat weight increases within the same quality tier?
- Larger diamonds are always cut with better proportions
- Large rough crystals suitable for bigger polished stones are rarer, increasing their per-carat scarcity premium (Correct answer)
- The cost of grading reports scales linearly with diamond size
- Larger diamonds always receive higher color grades due to greater light dispersion
Correct answer: Large rough crystals suitable for bigger polished stones are rarer, increasing their per-carat scarcity premium
Large gem-quality rough crystals are exponentially rarer than small ones, so the per-carat price rises with size to reflect the scarcity premium of finding and cutting larger stones.
Question 7: Which grading laboratory's reports typically command the highest price premium in the wholesale diamond market?
- IGI (International Gemological Institute)
- EGL (European Gemological Laboratory)
- GIA (Gemological Institute of America) (Correct answer)
- HRD (Hoge Raad voor Diamant)
Correct answer: GIA (Gemological Institute of America)
GIA reports are recognized as the industry gold standard for consistency and accuracy, commanding the highest market premiums and buyer confidence worldwide.
CDG Diamond Pricing & Valuation 1
What is the primary purpose of the Rapaport Diamond Report (Rap Sheet)?