CaratHunter
Plans
Cushion|Lab Grown|IGI

4.21ct D FL Cushion Lab Grown Diamond

EX • D/FL • IGI LG804605050

Shape and cutting style on the report: Cushion modified brilliant

Certificate IGI LG804605050

Diamond specifications and retailer prices

From £4,256 GBP
$5,702 USD
As of October 26, 2026
Save £21,552 GBP (84%) vs most expensive(unlock to see where)
21 retailers carry this diamond
Most expensive: £25,807 GBP at With Clarity · As of October 31, 2026
View at With Clarity

About this 4.21ct lab-grown cushion diamond

This 4.21ct 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 LG804605050 or 804605050. Listed at 21 retailers as of October 26, 2026, with prices from £4,256 to £25,807, a £21,552 spread on the same certified stone. With Clarity lists it at £25,807. 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

4.21
Carat
D
Colour
FL
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle35.5°
Pavilion angle37.5°
OriginLab Grown
Grading LabIGI
CertificateIGI LG804605050
Dimensions10.97 × 8.56 × 5.72 mm
L/W Ratio1.28
Girdle conditionFaceted
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
10.97 mm8.56 mm4.21 ctD / FL
OriginLab Grown
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG804605050
Side View
Table 61.0%Crown 35.5°Girdle: MED-STKPavilion 37.5°Culet: NoneDepth 66.8%

Caratlytics Score

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

Price History

Last verified: Oct 26
Current: £6,536 GBP|Low: £4,109 GBP|High: £25,318 GBP|Avg: £9,937 GBP|+0.3%
Retailer 1
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
Retailer 15
Retailer 16
Retailer 17
Retailer 18
With Clarity
October 31, 2026
Retailer 15£4,256 GBP
Retailer 5£4,730 GBP
Retailer 12£4,906 GBP
Retailer 3£5,000 GBP
Retailer 4£5,079 GBP
Retailer 2£5,082 GBP
Retailer 6£5,135 GBP
Retailer 1£6,536 GBP
Retailer 13£8,028 GBP
Retailer 17£8,599 GBP
Retailer 14£10,396 GBP
Retailer 11£10,816 GBP
Retailer 16£11,364 GBP
Retailer 7£13,106 GBP
Retailer 8£13,700 GBP
Retailer 9£14,137 GBP
Retailer 18£16,501 GBP
Retailer 10£17,795 GBP
With Clarity£25,318 GBP

40 data points across 19 retailers

21 retailers£4,256 GBP to £25,807 GBP

A
Cheapest Retailer
-
£4,256 GBP
$5,702 USD
A
Retailer 2
-
£4,730 GBP
CA$8,802 CAD
View
A
Retailer 3
-
£4,906 GBP
$6,573 USD
View
Final sale: no returns
A
Retailer 4
-
£5,000 GBP
$6,700 USD
View
A
Retailer 5
-
£5,079 GBP
$6,805 USD
View
Retailer 6
-
£5,082 GBP
$6,809 USD
View
Price last confirmed 15 days ago
A
Retailer 7
-
£5,135 GBP
$6,880 USD
View
A
Retailer 8
-
£6,536 GBP
View
B+
Retailer 9
-
£7,234 GBP
View
B+
Retailer 10
-
£8,028 GBP
€10,245 EUR
View
B+
Retailer 11
-
£8,599 GBP
$11,522 USD
View
B+
Retailer 12
-
£10,396 GBP
View
B+
Retailer 13
-
£10,816 GBP
ZAR 234,123 ZAR
View
B
Retailer 14
-
£11,364 GBP
$15,226 USD
View
B
Retailer 15
-
£13,106 GBP
$17,561 USD
View
B
Retailer 16
-
£13,700 GBP
$18,356 USD
View
B
Retailer 17
-
£14,137 GBP
$18,942 USD
View
B
Retailer 18
-
£14,944 GBP
$20,023 USD
View
B
Retailer 19
-
£16,501 GBP
$22,110 USD
View
B
Retailer 20
-
£17,795 GBP
$23,844 USD
View
Most Expensive
B
With Clarity
804605050 · Oct 31
£25,807 GBP
$34,579 USD
View
20 more retailers have this diamond
Prices start from £4,256 GBPSave up to £21,552 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
4.21ct Cushion
£4,256 GBP