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Cushion|Lab Grown|IGI

4.28ct D FL Cushion Lab Grown Diamond

ID • D/FL • IGI LG762545820

Shape and cutting style on the report: Cushion modified brilliant

Certificate IGI LG762545820

Diamond specifications and retailer prices

From £3,285 GBP
$4,401 USD
As of October 30, 2026
Save £11,423 GBP (78%) vs most expensive(unlock to see where)
14 retailers carry this diamond
Most expensive: £14,708 GBP at Blue Nile · As of October 31, 2026
View at Blue Nile

About this 4.28ct lab-grown cushion diamond

This 4.28ct lab-grown cushion sits in the three to five carat band, graded D colour (colourless) and FL clarity (flawless or internally-flawless), with a top-tier cut grade and certified by IGI LG762545820 or 762545820. Listed at 14 retailers as of October 30, 2026, with prices from £3,285 to £14,708, a £11,423 spread on the same certified stone. Blue Nile lists it at £14,708. Lab-grown prices in the 2ct and up range have fallen 40 to 60% over the last 18 months. Use the cross-retailer spread above to find the lowest current listing.

The 4Cs

4.28
Carat
D
Colour
FL
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle33.2°
Pavilion angle35.3°
OriginLab Grown
Grading LabIGI
CertificateIGI LG762545820
Dimensions10.79 × 8.75 × 5.75 mm
L/W Ratio1.23
Girdle conditionFaceted
Culet sizePointed
Cert comments
As Grown - No indication of post-growth treatment This Laboratory Grown Diamond was created by High Pressure High Temperature (HPHT) growth process Type II
Top View
10.79 mm8.75 mm4.28 ctD / FL
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG762545820
Side View
Table 58.0%Crown 33.2°Girdle: MED-THKPavilion 35.3°Culet: NoneDepth 65.7%

Caratlytics Score

How it works →
A
Excellent
Excellent quality and great value
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See the detailed 0 to 100 score with Quality, Value, Certification & Market breakdown

Price History

Last verified: Oct 30
Current: £14,708 GBP|Low: £3,285 GBP|High: £16,777 GBP|Avg: £8,348 GBP|+48.2%
Blue Nile
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
Retailer 13
Retailer 14
October 31, 2026
Retailer 7£3,285 GBP
Retailer 2£3,508 GBP
Retailer 13£4,815 GBP
Retailer 10£4,938 GBP
Retailer 5£6,094 GBP
Retailer 14£6,259 GBP
Retailer 6£6,426 GBP
Retailer 8£6,514 GBP
Retailer 12£8,105 GBP
Retailer 3£8,455 GBP
Retailer 9£9,896 GBP
Retailer 4£10,963 GBP
Retailer 11£13,585 GBP
Blue Nile£14,708 GBP

37 data points across 14 retailers

14 retailers£3,285 GBP to £14,708 GBP

A
Cheapest Retailer
-
£3,285 GBP
$4,401 USD
A
Retailer 2
-
£3,508 GBP
$4,701 USD
View
A
Retailer 3
-
£4,815 GBP
HK$50,400 HKD
View
A
Retailer 4
-
£4,938 GBP
View
Retailer 5
-
£6,094 GBP
$8,165 USD
View
Price last confirmed 12 days ago
A
Retailer 6
-
£6,259 GBP
€7,987 EUR
View
A
Retailer 7
-
£6,426 GBP
$8,610 USD
View
A
Retailer 8
-
£6,514 GBP
$8,728 USD
View
B+
Retailer 9
-
£8,105 GBP
ZAR 175,446 ZAR
View
B+
Retailer 10
-
£8,455 GBP
View
B+
Retailer 11
-
£9,896 GBP
$13,260 USD
View
B+
Retailer 12
-
£10,963 GBP
$14,689 USD
View
B
Retailer 13
-
£13,585 GBP
$18,203 USD
View
Most Expensive
B
Blue Nile
29977365 · Oct 31
£14,708 GBP
$19,707 USD
View
13 more retailers have this diamond
Prices start from £3,285 GBPSave up to £11,423 GBP

Carat Hunter is not affiliated with, endorsed by, or sponsored by any retailer listed. Retailer information is from publicly available sources and may not be current. Verify details directly with the retailer before purchasing. Return terms as we hold them. Check the retailer's own returns page before you buy.

A
4.28ct Cushion
£3,285 GBP