Radiant|Lab Grown|IGI

1.78ct F SI1 Radiant Lab Grown Diamond

ID • F/SI1 • IGI LG780619896

Shape and cutting style on the report: Cut cornered rectangular modified brilliant

Certificate IGI LG780619896

Diamond specifications and retailer prices

From £149 GBP

$200 USD

As of November 1, 2026

Save £1,133 GBP (88%) vs most expensive(unlock to see where)

15 retailers carry this diamond

Most expensive: £1,282 GBP at Do Amore Diamonds · As of November 2, 2026

View at Do Amore Diamonds

About this 1.78ct lab-grown radiant diamond

This 1.78ct lab-grown radiant sits in the one-and-a-half to two carat band, graded F colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG780619896 or 780619896. Listed at 15 retailers as of November 1, 2026, with prices from £149 to £1,282, a £1,133 spread on the same certified stone. Do Amore Diamonds lists it at £1,282. 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

1.78

Carat

Colour

SI1

Clarity

Ideal

Cut

Specifications

CutIdeal

PolishExcellent

SymmetryExcellent

FluorescenceNone

Crown angle37.6°

Pavilion angle37°

OriginLab Grown

Grading LabIGI

CertificateIGI LG780619896

Dimensions8.34 × 6.27 × 4.19 mm

L/W Ratio1.33

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

View IGI Report →View Loupe360 Video →

Top View

OriginLab Grown

CutIdeal

PolishExcellent

SymmetryExcellent

FluorescenceNone

CertificateIGI LG780619896

Side View

Caratlytics Score

How it works →

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: Nov 1

Current: £1,282 GBP|Low: £139 GBP|High: £1,334 GBP|Avg: £583 GBP|+4.2%

Do Amore Diamonds

Retailer 2

Retailer 3

Retailer 4

Retailer 5

Retailer 6

Retailer 7

Retailer 8

Retailer 9

Retailer 10

Retailer 11

November 2, 2026

Retailer 8£149 GBP

Retailer 11£196 GBP

Retailer 7£226 GBP

Retailer 5£302 GBP

Retailer 10£367 GBP

Retailer 2£475 GBP

Retailer 9£591 GBP

Retailer 3£820 GBP

Retailer 4£853 GBP

Retailer 6£872 GBP

Do Amore Diamonds£1,282 GBP

27 data points across 11 retailers

15 retailers£149 GBP to £1,282 GBP

Retailer 1

£133 GBP

$179 USD

Price last confirmed 31 days ago

Retailer 2

£149 GBP

$200 USD

View

Final sale: no returns

Retailer 3

£156 GBP

$210 USD

View

Price last confirmed 36 days ago

Retailer 4

£196 GBP

$263 USD

View

B+

Retailer 5

£226 GBP

$303 USD

View

Retailer 6

£302 GBP

€386 EUR

View

Retailer 7

£367 GBP

$492 USD

View

Retailer 8

£475 GBP

$637 USD

View

B+

Retailer 9

£591 GBP

$793 USD

View

Retailer 10

£610 GBP

$819 USD

View

Price last confirmed 32 days ago

B+

Retailer 11

£741 GBP

$995 USD

View

B+

Retailer 12

£820 GBP

$1,100 USD

View

B+

Retailer 13

£853 GBP

View

Retailer 14

£872 GBP

$1,170 USD

View

Most Expensive

Do Amore Diamonds

27-93711A3C9 · Nov 2

£1,282 GBP

$1,720 USD

View

14 more retailers have this diamond

Prices start from £149 GBPSave up to £1,133 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.

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