Magnificent Jewels and Noble Jewels
Pre-Auction Analysis: May 16th, 2023, Sotheby’s Geneva, Magnificent Jewels and Noble Jewels
Our Sotheby’s Geneva, Pre-Auction Analysis focuses on elements that are not always visible to the untrained eye. We discuss characteristics such as Inner-Grade, Color Dispersion, and Undertone – collectively termed IDU. Professionals use the IDU method intuitively when analyzing a Fancy Color Diamond. The acronym we use makes these elements easier to remember.
Members who read this analysis should see it as a valuable supplement to the GIA report. A detailed explanation of the FCRF’s grading methodology can be found at the end of this article. We recommend reviewing it closely to broaden one’s professional vocabulary for describing fancy color diamonds to clients.
Please note that we analyze and grade diamonds under LED lights and relative to their grade on the GIA report.
The Grades
We use grades 1, 2, 3, and 4, with 1 being the lowest grade. Grade “4+” is granted in rare cases and denotes stones with exceptional characteristics. Stones that receive a minimum total IDU score of 9 without a red remark pass the industry premium threshold and can be traded easily. Fancy Color Diamonds that are graded 10 or above (without a quality remark) are usually sought after by high-end jewelers and collectors.
For your convenience, we have added direct links to diamonds’ GIA reports and FCRF rarity stats.
- All images in this analysis were taken with an iPhone 13 Pro; no filters were applied.
- All auction valuations are per-carat and listed in US Dollars.
Disclaimer
This analysis reflects the opinions of the FCRF professional team. It does not constitute a recommendation to buy or not buy a particular diamond. Buyers assume the responsibility of verifying any information with the auction house. At times, mistakes can happen in the visual analysis and report placement. Therefore, one should not rely solely on this analysis for buying purposes.
__________________________________________________________________________
Lot: 540
Description: A Pair of Fancy Vivid Yellow diamond earrings weighing 3.01 and 3.0, vivid yellow, VS clarity
Analysis:
Two heart-shaped diamonds with different dimensions and outlines. The inner grade is strong in both diamonds, and no undertone is visible in the hue.
High Auction Estimation: $ 42,645 pc
Price realized: $33,055 pc
Visual Assets:
Inner Grade..……………….3
Color Dispersion.………4
Undertone..…………………4
Total Visual Score….11 out of 12
__________________________________________________________________________
Lot: 541
Description: Two pink diamonds ring with different saturations.
1.04 ct, Radiant, Fancy Intense Purplish Pink, I2 Rarity , GIA
1.05 ct, Radiant, Fancy Deep Purplish Pink, I1 Rarity , GIA
Analysis:
Two pink radiant-cut diamonds. A 1.04 carat fancy intense purplish pink with an I2 clarity grade and 74% depth, while the other is a fancy deep purplish pink with an I1 clarity and 75% depth. Both stones have a strong inner grade and an attractive undertone due to the purple modifier. Despite their weight, both stones appear smaller than a one carat, and the inclusions are visible to the naked eye.
High Auction Estimation: $ 147,069 pc
Didn’t reach the minimum
Visual Assets:
Inner Grade..……………….3
Color Dispersion.………3
Undertone..…………………4
Total Visual Score….10 out of 12
Quality remark: I1 AND I2 CLARITY-74%/75% depth
_________________________________________________________________________
Lot: 542
Description: A three stone ring with a 14.17 ct, Fancy Yellow, Pear, VS1
Analysis:
A 14.17-carat brilliant pear-shaped diamond with very low color dispersion concentrated in the point and rounded area. The inner-grade is solid with a slight green undertone. The diamond has strong blue fluorescence.
High Auction Estimation: $ 13,373 pc
Price realized: $11,022 pc
Rarity: 3-5 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….3
Color Dispersion.…….…1
Undertone..…………………2
Total Visual Score….6 out of 12
Quality remark: low dispersion, strong blue fluo
__________________________________________________________________________
Lot: 548
Description: A three stone ring with a fancy light yellow pear-shape weighing 15.39 ct, VS2
Analysis:
An elongated pear-shaped diamond with a ratio of 1:1.88. A few colorless areas are visible on the crown, and the inner-grade is strong (one should take into account the yellow gold covering the pavilion). No significant undertone is visible in the hue.
High Auction Estimation: $ 19,970 pc
Didn’t reach the minimum
Rarity: 2-5 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….4
Color Dispersion.………3
Undertone..…………………3
Total Visual Score….10 out of 12
__________________________________________________________________________
Lot: 549
Description: A ring with a 11.34 ct, Fancy Vivid Yellow, rounded corner step cut, VS1
Analysis:
An unconventional shaped diamond with an outline of a cushion and step-cut facet alignment. The diamond’s outline is not symmetrical and not aligned with its pavilion. The inner-grade is strong, and no significant undertone is visible. The symmetry grade on the GIA report is Fair.
High Auction Estimation: $ 64,061 pc
Price realized: $75,142 pc
Rarity: N/A
GIA Report: View
Visual Assets:
Inner Grade..……………….4
Color Dispersion.………3
Undertone..…………………3
Total Visual Score….10 out of 12
Quality remark: Fair symmetry
__________________________________________________________________________
Lot: 555
Description: 12.02 ct, Fancy Intense Yellow, Radiant, VS2
Analysis:
A square rounded corner, fancy intense yellow with a colorless crown. The inner-grade is very strong and no significant undertone is visible in the hue.
High Auction Estimation: $ 21,322 pc
Price realized: $23,029 pc
Rarity: 4-7 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….4
Color Dispersion.………3
Undertone..…………………3
Total Visual Score….10 out of 12
_________________________________________________________________________
Lot: 564
Description: 4.02 ct, Fancy Vivid Yellow, Emerald, VS1
Analysis:
A vivid yellow, emerald-cut diamond with a ratio of 1:1.34 and a 72% depth. The diamond is polished without any modification to reinforce color, thus exhibiting low color dispersion with a colorless center. The inner-grade appears to be weak. Due to the mounting and the gold covering the pavilion, it is impossible to analyze the undertone.
High Auction Estimation: $ 51,282 pc
Price realized: $52,962 pc
Rarity: 4-7 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….2
Color Dispersion.………2
Undertone..…………………N/A
Total Visual Score….N/A out of 12
__________________________________________________________________________
Lot: 574
Description: 11.57 ct, Fancy Vivid Yellow, Emerald, VVS2
Analysis:
An Emerald cut diamond with a 1 : 1.21 ratio. The stone is polished without any modification to reinforce the saturation creating large colorless areas. The undertone is extremely high and due to the classic facet alignment the color dispersion is low.
High Auction Estimation: $ 52,972 pc
Price realized: $109,160 pc
Rarity: 2-5 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….4+
Color Dispersion.………2
Undertone..…………………3
Total Visual Score….9 out of 12
Quality remark: low color dispersion
__________________________________________________________________________
Lot: 580
Description: A ring with a 1.91 ct, Fancy Dark Bluish Gray, Round, VVS1
Analysis:
A fancy Dark Gray round brilliant cut with a blue modifier. The blue addition is quite prominent and gives a blue sensation under direct sunlight. As opposed to most grey diamonds, the diamond’s crystal is highly translucent.
High Auction Estimation: $ 52,667 pc
Price realized: $81,714 pc
Rarity: Once every 8-12 years – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….4
Color Dispersion.………4
Undertone..…………………4
Total Visual Score….12 out of 12
_________________________________________________________________________
Lot: 621
Fancy yellow and coloured diamond necklace with a total of 49 stones.
The largest central diamond weighs 10.01 carats with GIA report.
Description: 10.01 ct, Fancy Yellow, Heart, VVS2
Analysis:
A large necklace of yellow fancy color heart-shaped diamonds. Most diamonds in this layout have a sloppy outline, a very high crown, and low dispersion.
High Auction Estimation: $424,097 Total
Price realized: $454,246 Total
Rarity: 1-2 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….N/A
Color Dispersion.………N/A
Undertone..…………………N/A
Total Visual Score….N/A out of 12
_________________________________________________________________________
Lot: 634
Description: A large necklace and earrings with various Yellow fancy color diamonds brilliant-cut, pear- and marquise-shaped diamonds, supporting a fringe set with three step-cut fancy yellow or fancy intense yellow diamonds weighing 14.31, 6.19 and 6.08 carats, further enhanced with step-cut and pear-shaped diamonds of yellow tint, length approximately 370mm, and a pair of pendent ear clips similarly set with step-cut fancy intense yellow diamonds weighing 7.06 and 6.56 carats respectively.
Analysis:
A very large necklace with 10 fancy intense and fancy yellow radiant cut center diamonds. All Radiant cut diamonds are polished consistently with the same proportions. All diamonds have a small colorless crown and appear larger in relation to their carat weight.
Total High Auction Estimation: $ 55,963 pc
Didn’t reach the minimum
Rarity: N/A
5 GIA Reports: View
Visual Assets:
Inner Grade..……………….N/A
Color Dispersion.………N/A
Undertone..…………………N/A
Total Visual Score….N/A out of 12
__________________________________________________________________________
Lot: 657
Description: 32.20 ct, Fancy Intense Yellow, Cushion, VVS2
Analysis:
A large vivid yellow cushion-cut diamond with a 57% depth. Most of the crown is colorless, leaving the color concentrated in the table. The inner-grade is solid; however, the gold covering the pavilion enhances the saturation to some degree. No prominent undertone is visible in the hue.
A laser inscription stating “Graff” is present on the girdle.
High Auction Estimation: $ 38,196 pc
Price realized: $30,810 pc
Rarity: 1-2 diamonds yearly – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….3
Color Dispersion.………2
Undertone..…………………4
Total Visual Score….9 out of 12
Quality remark: low color dispersion
__________________________________________________________________________
Lot: 664
Description: 5.01 ct, Fancy Vivid Purplish Pink, Radiant, VS2
Analysis:
A rare size for any vivid purplish pink. The symmetry is Fair with a depth of 80%, creating a relatively small face up for a 5 carat radiant cut. The inner-grade is strong and the purple modifier creates a pleasant color sensation.
High Auction Estimation: $ 1,635,889 pc
Price realized: $1,251,380 pc
Rarity: Once every 10-11 years – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….3
Color Dispersion.………4
Undertone..…………………4
Total Visual Score….11 out of 12
Quality remark: 80% depth, fair symmetry
__________________________________________________________________________
Lot: 667
Description: 74.76 ct, Fancy Vivid Yellow, Cushion, SI1 Rarity , GIA
Analysis:
A large Fancy intense yellow cushion cut diamond with a 78% depth. A large, visible inclusion is situated under the table. The crown is extremely high and creates large colorless areas. The inner-grade is low.
GIA report is dated 2015.
High Auction Estimation: $ 48,148 pc
Didn’t reach the minimum
Visual Assets:
Inner Grade..……………….2
Color Dispersion.………2
Undertone..…………………3
Total Visual Score….7 out of 12
Quality remark: low dispersion, visible inclusion
__________________________________________________________________________
Lot: 673
Description: 21.94 ct, Fancy Intense Pink, Radiant, VVS2
Analysis:
A large fancy intense pink radiant cut diamond. According to the facet alignment and the colorless crown we assume it was cut and polished from what used to be a round brilliant cut, to reinforce saturation. The inner grade is not strong and the undertone is average.
The diamond’s crystal has a fair amount of graining, causing some degree of haziness. Graining lines causing this cloudiness are also responsible for the VVS clarity. The depth percentage is 58.8, and the face-up view of the stone appears larger in relation to its weight.
High Auction Estimation: $ 559,908 pc
Price realized: $537,252 pc
Rarity: Once every 25 years or more – Share this rarity result – Here
GIA Report: View
Visual Assets:
Inner Grade..……………….2
Color Dispersion.………3
Undertone..…………………3
Total Visual Score….8 out of 12
_________________________________________________________________________
Lot: 675
Description: 11.16 ct, Fancy Vivid Blue, Pear
Analysis:
A rare size for a vivid blue diamond. The classic Brilliant-cut facet alignment creates a low color dispersion with a large colorless “bowtine”, an indication it was probably cut and polished before the 90s. The Inner-grade is average and a small amount of grey undertone is present in the hue.
High Auction Estimation: N/A
Price realized: $2,263,110 pc
Rarity: N/A
GIA Report: View
Visual Assets:
Inner Grade..……………….3
Color Dispersion.………2
Undertone..…………………3
Total Visual Score….8 out of 12
Quality remark: low color dispersion
__________________________________________________________________________
General
We use 1, 2, 3, 4, and 4+ to grade the three visual elements that GIA is silent about, although they impact the value dramatically.
Inner-Grade refers to the strength of color within each GIA saturation category:
Grade 1 weakest, bordering the saturation below.
Grade 2 weak (most common).
Grade 3 full-bodied color (above average).
Grade 4 very strong saturation.
Grade 4+ applies to the vivid category only, exhibiting the strongest possible saturation (rarely seen).
Undertone refers to a subtle hue influence in the body color of the stone.
For example:
A Fancy Blue Diamond with a significant gray presence in its general appearance will be graded with a low undertone grade of 1. A Fancy Blue that has no gray influence that is close to a primary blue will receive the grade, 4.
In a Pink Fancy Color Diamond, a stone with a warm undertone (such as orange or brown) will receive a low undertone grade. A pink stone with a cold undertone (such as purple) will receive a high grade.
In Yellow Fancy Color Diamonds, low foreign influence or a light orange influence will grant the stone a high undertone grade. When the yellow undertone looks like a true primary yellow, it will receive the rare grade 4+. Green and brown undertones will grant a low grade in the yellow category.
Color Dispersion relates to how well the color is dispersed in the face-up view of a Fancy Color Diamond, regardless as to whether the GIA grades the stone as even. A stone with many colorless areas will receive the grade 1, while a stone that exhibits its face-up view with no colorless patches will receive the grade 4+. Unlike the first two elements, the color dispersion is not a gemological quality and is the result of cutter proficiency.
You reached your free article limit. Click here to join the FCRF and enjoy all our articles and innovative tools & services.
The article has been sent to your email address. Enjoy!
