wheel / two-color grade · dominant Gray
Blue-gray
Group share
3%
Blue-gray group
Exact count
Not disclosed
GIA publishes group shares, not per-grade counts
Median USD per carat
$31.6k
n=3 included + 2 qualified · $4.4k–$32.9k · 0.29–2.33 ct · 1997–2001
Rarity-adjusted value
insufficient data
two-color grades have no published population
auction sales by intensity5 sales
- Fancy Deep—
- Fancy Vivid—
- Fancy Intense—
- Fancy$4.4k/ct · 0.29 ct · 1999$31.6k/ct · 1.43 ct · 2001$32.9k/ct · 2.33 ct · 1997$113k/ct · 3.01 ct · 2020$166k/ct · 3.01 ct · 2019
- Fancy Light—
price by intensity
| Intensity | Included n | Median $/ct | Mean $/ct | Low – high | Since 2020 | Qualified | Study stones | Share of cohort |
|---|---|---|---|---|---|---|---|---|
| Fancy Light | — | — | — | — | — | — | — | — |
| Fancy | 3 | $31.6k | $23.0k | $4.4k – $32.9k | — | $140k · n=2 | — | — |
| Fancy Intense | — | — | — | — | — | — | — | — |
| Fancy Vivid | — | — | — | — | — | — | — | — |
| Fancy Deep | — | — | — | — | — | — | — | — |
methodologyshow
read before interpreting
Group label. Blue-gray versus bluish gray allocation is not disclosed.
related grades
auction sales3 included · 2 qualified
| ID | Intensity | Lot / stone | Carats | Clarity | Sale | Realised | USD / ct | Status | Sources |
|---|---|---|---|---|---|---|---|---|---|
| A397 | Fancy | AN UNMOUNTED RECTANGULAR-CUT FANCY BLUE-GREY DIAMOND Loose diamond. Source spells hue Blue-Grey; normalized to American gray without changing modifier order. | 2.33 ct | I1 | Christie's Geneva · 20 May 1997 | CHF 108,000 $76,732 · FRED local units per USD; sale date | $32.9k | Included | lot · fx |
| A447 | Fancy | UNMOUNTED FANCY BLUE-GRAY MARQUISE-CUT DIAMOND Loose marquise-cut diamond; source American spelling retained. | 0.29 ct | Not stated | Christie's New York (Christie’s East) · 11 Feb 1999 | USD 1,265 $1,265 · USD as reported | $4.4k | Included | lot |
| A702 | Fancy | AN UNMOUNTED RECTANGULAR-CUT FANCY BLUE-GRAY DIAMOND Whole-lot auction result divided by target carats; setting and accents are not deducted. | 1.43 ct | VS1 | Christie's Hong Kong · 1 May 2001 | HKD 352,500 $45,196 · FRED local units per USD; sale date | $31.6k | Included | lot · fx |
| A152 | Fancy | An Important Fancy Coloured Diamond Necklace Whole-lot price divided by target colored carat weight; mounting, accents and signature are included. Necklace also contains numerous other colored diamonds; blue-gray target cannot be isolated. Natural color origin not explicitly repeated in the accessible catalog; retained as a qualified catalog observation, not a verified natural-color sample. | 3.01 ct | SI1 | Phillips Hong Kong · 28 Nov 2020 | HKD 2,646,000 $341,384 · FRED local units per USD; prior business day | $113k | Qualified | lot · fx |
| A203 | Fancy | An Important Fancy Diamond, Colored Diamond and Gold Necklace Whole-lot price divided by target colored carat weight; mounting, accents and signature are included. Necklace also contains numerous other colored diamonds; blue-gray target cannot be isolated. Natural color origin not explicitly repeated in the accessible catalog; retained as a qualified catalog observation, not a verified natural-color sample. | 3.01 ct | SI1 | Phillips New York · 9 Dec 2019 | USD 500,000 $500,000 · USD as reported | $166k | Qualified | lot |
supply evidence
this exact grade
| ID | Cohort | Intensity bin | Stones | Share | Period · scope | Limits | Source |
|---|---|---|---|---|---|---|---|
| S093 | Blue-gray | Individual intensity bins | — | — | Reviewed GIA papers, 2002–2025 Evidence gap for exact grade | An all-intensity hue count or pooled-family distribution does not disclose this exact hue’s distribution. Blank numeric cells mean unavailable, not zero. | See GIA Evidence hue cohorts |
evidence
R18
G3
Blue-gray group3% of >15,000Exact count not stated
>15,000 blue/gray/violet study submissions · Pre-2018 study; last decade
Group label. Blue-gray versus bluish gray allocation is not disclosed.