CaratHunter
Plans
Cushion|Lab Grown|IGI

1.56ct E SI1 Cushion Lab Grown Diamond

ID • E/SI1 • IGI LG683597087

Shape and cutting style on the report: Square cushion brilliant

Certificate IGI LG683597087

Diamond specifications and retailer prices

From £317 GBP
$422 USD
As of October 28, 2026
Save £855 GBP (73%) vs most expensive(unlock to see where)
8 retailers carry this diamond
Most expensive: £1,171 GBP at Brilliant Earth · As of October 29, 2026
View at Brilliant Earth

About this 1.56ct lab-grown cushion diamond

This 1.56ct lab-grown cushion sits in the one-and-a-half to two carat band, graded E colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG683597087 or 683597087. Listed at 8 retailers as of October 28, 2026, with prices from £317 to £1,171, a £855 spread on the same certified stone. Brilliant Earth lists it at £1,171. 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

1.56
Carat
E
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle37.2°
Pavilion angle37.1°
OriginLab Grown
Grading LabIGI
CertificateIGI LG683597087
Dimensions6.60 × 6.58 × 4.47 mm
L/W Ratio1.00
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
6.60 mm6.58 mm1.56 ctE / SI1
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG683597087
Side View
Table 62.0%Crown 37.2°Girdle: THN-MEDPavilion 37.1°Culet: NoneDepth 67.9%

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 28
Current: £1,171 GBP|Low: £298 GBP|High: £1,209 GBP|Avg: £540 GBP
Brilliant Earth
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
October 29, 2026
Retailer 6£317 GBP
Retailer 2£332 GBP
Retailer 3£348 GBP
Retailer 8£359 GBP
Retailer 7£376 GBP
Retailer 5£661 GBP
Retailer 4£851 GBP
Brilliant Earth£1,171 GBP

41 data points across 8 retailers

8 retailers£317 GBP to £1,171 GBP

B+
Cheapest Retailer
-
£317 GBP
$422 USD
A
Retailer 2
-
£332 GBP
View
A
Retailer 3
-
£348 GBP
€441 EUR
View
A
Retailer 4
-
£359 GBP
$478 USD
View
A
Retailer 5
-
£376 GBP
$501 USD
View
Retailer 6
-
£661 GBP
$880 USD
View
Price last confirmed 10 days ago
B
Retailer 7
-
£851 GBP
View
Most Expensive
B
Brilliant Earth
13446550A · Oct 29
£1,171 GBP
$1,560 USD
View
7 more retailers have this diamond
Prices start from £317 GBPSave up to £855 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
1.56ct Cushion
£317 GBP