Cushion|Lab Grown|IGI

5.18ct D IF Cushion Lab Grown Diamond

ID • D/IF

Diamond specifications and retailer prices

From $16,279 USD

As of October 31, 2026

2 retailers carry this diamond

Most expensive: $16,279 USD at Blue Nile

View at Blue Nile

About this 5.18ct lab-grown cushion diamond

This 5.18ct lab-grown cushion sits in the over five carat band, graded D colour (colourless) and IF clarity (flawless or internally-flawless), with a top-tier cut grade and certified by IGI. Listed at 2 retailers as of October 31, 2026. 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

5.18

Carat

Color

Clarity

Ideal

Cut

Specifications

CutIdeal

PolishExcellent

SymmetryExcellent

FluorescenceNone

OriginLab Grown

Grading LabIGI

Dimensions11.71 × 7.95 × 5.11 mm

L/W Ratio1.47

Top View

OriginLab Grown

CutIdeal

PolishExcellent

SymmetryExcellent

FluorescenceNone

CertificateIGI

Side View

Caratlytics Score

How it works →

B+

Very Good

Strong quality and value balance

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Price History

Last verified: Oct 31

Current: $16,279 USD|Low: $6,481 USD|High: $19,560 USD|Avg: $13,580 USD|+9.9%

Blue Nile

Retailer 2

Retailer 3

October 31, 2026

Retailer 2$6,481 USD

Blue Nile$16,279 USD

Retailer 3$19,560 USD

35 data points across 3 retailers

2 retailers

Retailer 1

$6,481 USD

Price last confirmed 10 days ago

Most Expensive

B+

Blue Nile

28013504 · Oct 31

$16,279 USD

View

1 more retailer has this diamond

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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B+

5.18ct Cushion

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