CaratHunter
Plans
Oval|Lab Grown|IGI

1.66ct D SI1 Oval Lab Grown Diamond

ID • D/SI1 • IGI LG520284681

Shape and cutting style on the report: Oval brilliant

Certificate IGI LG520284681

Diamond specifications and retailer prices

From £163 GBP
$219 USD
As of November 1, 2026
Save £791 GBP (83%) vs most expensive(unlock to see where)
17 retailers carry this diamond
Most expensive: £954 GBP at Brilliant Earth · As of November 2, 2026
View at Brilliant Earth

About this 1.66ct lab-grown oval diamond

This 1.66ct lab-grown oval sits in the one-and-a-half to two carat band, graded D colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG520284681 or 520284681. Listed at 17 retailers as of November 1, 2026, with prices from £163 to £954, a £791 spread on the same certified stone. Brilliant Earth lists it at £954. SI-grade stones are eye-clean roughly 60 to 70% of the time at this carat range. Check the inclusion plot on the cert and ask the retailer for high-resolution video before buying.

The 4Cs

1.66
Carat
D
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle36.5°
Pavilion angle39.4°
OriginLab Grown
Grading LabIGI
CertificateIGI LG520284681
Dimensions9.55 × 6.80 × 4.10 mm
L/W Ratio1.40
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
9.55 mm6.80 mm1.66 ctD / SI1
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG520284681
Side View
Table 60.5%Crown 36.5°Girdle: MED-STKPavilion 39.4°Culet: NoneDepth 60.3%

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: Nov 1
Current: £954 GBP|Low: £163 GBP|High: £954 GBP|Avg: £474 GBP
Brilliant Earth
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
November 2, 2026
Retailer 8£163 GBP
Retailer 6£183 GBP
Retailer 5£189 GBP
Retailer 14£202 GBP
Retailer 2£225 GBP
Retailer 16£272 GBP
Retailer 9£376 GBP
Retailer 12£394 GBP
Retailer 15£396 GBP
Retailer 4£435 GBP
Retailer 3£650 GBP
Retailer 13£652 GBP
Retailer 7£689 GBP
Retailer 10£723 GBP
Retailer 11£810 GBP
Brilliant Earth£954 GBP

36 data points across 16 retailers

17 retailers£163 GBP to £954 GBP

A
Cheapest Retailer
-
£163 GBP
$219 USD
A
Retailer 2
-
£183 GBP
$245 USD
View
Final sale: no returns
A
Retailer 3
-
£189 GBP
$254 USD
View
A
Retailer 4
-
£202 GBP
$271 USD
View
Retailer 5
-
£218 GBP
$293 USD
View
Price last confirmed 8 days ago
A
Retailer 6
-
£225 GBP
View
B+
Retailer 7
-
£272 GBP
$365 USD
View
A
Retailer 8
-
£376 GBP
View
A
Retailer 9
-
£394 GBP
€503 EUR
View
A
Retailer 10
-
£396 GBP
$531 USD
View
B+
Retailer 11
-
£435 GBP
$584 USD
View
B+
Retailer 12
-
£650 GBP
$872 USD
View
B+
Retailer 13
-
£652 GBP
$875 USD
View
B+
Retailer 14
-
£689 GBP
$925 USD
View
B+
Retailer 15
-
£723 GBP
$970 USD
View
B
Retailer 16
-
£810 GBP
View
Most Expensive
B
Brilliant Earth
11225627A · Nov 2
£954 GBP
$1,280 USD
View
16 more retailers have this diamond
Prices start from £163 GBPSave up to £791 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
1.66ct Oval
£163 GBP