Home 3 Carat Lab Grown Diamond Rings

3 Carat Lab Grown Diamond Rings

Complete engagement rings with the IGI certified lab grown diamond already set, made to order in our Los Angeles atelier at one price.

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Duran Select Round Platinum

The Duran Select Simple Bezel Solitaire Round Lab Diamond Engagement Ring in Platinum

Select Simple Bezel Solitaire Round · Platinum

From $3,515

Lab Diamond Included
Sade Select Halo Marquise Lab Diamond Engagement Ring in 14K Rose Gold, on hand, angled | RockHer

The Sade Select Halo Marquise Lab Diamond Engagement Ring in 14K Rose Gold

Select Halo Marquise · 14K Rose Gold

From $3,760

Lab Diamond Included
Tina Select Cushion 18K White Gold

The Tina Select Triple Row Pavé Cushion Cut Lab Diamond Engagement Ring in 18K White Gold

Select Triple Row Pavé Cushion Cut · 18K White Gold

From $4,640

Lab Diamond Included
Alice Select Round 18K Yellow Gold

The Alice Select Twisted Three Stone Solitaire Round Lab Diamond Engagement Ring in 18K Yellow Gold

Select Twisted Three Stone Solitaire Round · 18K Yellow Gold

From $5,050

Lab Diamond Included
Taylor Select Pavé Halo Round Lab Diamond Engagement Ring in 14K Rose Gold, alternate angle | RockHer

The Taylor Select Pavé Halo Round Lab Diamond Engagement Ring in 14K Rose Gold

Select Pavé Halo Round · 14K Rose Gold

From $4,740

Lab Diamond Included
Dylan Select Halo Asscher Cut Lab Diamond Engagement Ring in 18K Yellow Gold, shown on hand, angled | RockHer

The Dylan Select Halo Asscher Cut Lab Diamond Engagement Ring in 18K Yellow Gold

Select Halo Asscher Cut · 18K Yellow Gold

From $3,580

Lab Diamond Included
Angelica Select Marquise 18K Yellow Gold

The Angelica Select Three Stone Matched Solitaire Marquise Lab Diamond Engagement Ring in 18K Yellow Gold

Select Three Stone Matched Solitaire Marquise · 18K Yellow Gold

From $8,255

Lab Diamond Included
Aria Select Round Platinum

The Aria Select Channel Row Pavé Halo Round Lab Diamond Engagement Ring in Platinum

Select Channel Row Pavé Halo Round · Platinum

From $6,360

Lab Diamond Included
Amy Select High Polish Simple Halo Round Lab Diamond Engagement Ring in 18K Yellow Gold, shown on hand, angled | RockHer

The Amy Select High Polish Simple Halo Round Lab Diamond Engagement Ring in 18K Yellow Gold

Select High Polish Simple Halo Round · 18K Yellow Gold

From $4,420

Lab Diamond Included
Ariana Select Round Platinum

The Ariana Select Swirl Halo Round Lab Diamond Engagement Ring in Platinum

Select Swirl Halo Round · Platinum

From $5,620

Lab Diamond Included
Annabelle Select Pavé Oval Lab Diamond Engagement Ring in 18K Yellow Gold, shown on hand, angled | RockHer

The Annabelle Select Pavé Oval Lab Diamond Engagement Ring in 18K Yellow Gold

Select Pavé Oval · 18K Yellow Gold

From $4,285

Lab Diamond Included
Bess Select Round Platinum

The Bess Select Love Knot Pavé Halo Round Lab Diamond Engagement Ring in Platinum

Select Love Knot Pavé Halo Round · Platinum

From $7,380

Lab Diamond Included
Elliott Select Oval 18K White Gold

The Elliott Select Hidden Halo Pavé Oval Lab Diamond Engagement Ring in 18K White Gold

Select Hidden Halo Pavé Oval · 18K White Gold

From $4,120

Lab Diamond Included
Billie Select Halo Round Lab Diamond Engagement Ring in 18K Yellow Gold, on hand, angled | RockHer

The Billie Select Halo Round Lab Diamond Engagement Ring in 18K Yellow Gold

Select Halo Round · 18K Yellow Gold

From $4,975

Lab Diamond Included
The Eartha radiant engagement ring setting in 18K Yellow Gold | RockHer

The Eartha Select Upper Hidden Halo Solitaire Radiant Cut Lab Diamond Engagement Ring in 18K Yellow Gold

Select Upper Hidden Halo Solitaire Radiant Cut · 18K Yellow Gold

From $3,430

Lab Diamond Included
Etta Select Halo Oval Lab Diamond Engagement Ring in 14K Rose Gold, on hand, angled | RockHer

The Etta Select Halo Oval Lab Diamond Engagement Ring in 14K Rose Gold

Select Halo Oval · 14K Rose Gold

From $4,030

Lab Diamond Included
Olivia Select Round Platinum

The Olivia Select Pavé Round Lab Diamond Engagement Ring in Platinum

Select Pavé Round · Platinum

From $4,300

Lab Diamond Included
Mae Select Round 14K Rose Gold

The Mae Select Vintage Beaded Solitaire Round Lab Diamond Engagement Ring in 14K Rose Gold

Select Vintage Beaded Solitaire Round · 14K Rose Gold

From $5,405

Lab Diamond Included
Ivy Select Halo Oval Lab Diamond Engagement Ring in 14K Rose Gold, shown on hand, angled | RockHer

The Ivy Select Halo Oval Lab Diamond Engagement Ring in 14K Rose Gold

Select Halo Oval · 14K Rose Gold

From $4,370

Lab Diamond Included
Everly Select Round Platinum

The Everly Select Pav Halo Round Lab Diamond Engagement Ring in Platinum

Select Pav Halo Round · Platinum

From $5,140

Lab Diamond Included
Jennifer Select Round 18K Yellow Gold

The Jennifer Select Three Stone With Halo Round Lab Diamond Engagement Ring in 18K Yellow Gold

Select Three Stone With Halo Round · 18K Yellow Gold

From $5,340

Lab Diamond Included
Ella Select Oval Platinum

The Ella Select Pav Halo Oval Lab Diamond Engagement Ring in Platinum

Select Pav Halo Oval · Platinum

From $7,020

Lab Diamond Included
Violetta Select Round 18K White Gold

The Violetta Select Multi Layer Interweave Pavé Solitaire Round Lab Diamond Engagement Ring in 18K White Gold

Select Multi Layer Interweave Pavé Solitaire Round · 18K White Gold

From $7,635

Lab Diamond Included
Gladys Select Round 18K Yellow Gold

The Gladys Select Solitaire Round Lab Diamond Engagement Ring in 18K Yellow Gold

Select Solitaire Round · 18K Yellow Gold

From $3,760

Lab Diamond Included
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Complete Lab Diamond Engagement Rings Made to Order in Los Angeles

RockHer Select engagement rings arrive complete: a made to order setting in solid gold or platinum with an IGI certified lab grown diamond already matched and set by our gemologists, each one scored by ROSI™, gemological intelligence, before it ships. One fair price, a 40 day return window on eligible pieces, one complimentary resize within 60 days of delivery, up to 1.5 sizes (U.S.), and a lifetime warranty against manufacturing defects.

Speak with a Gemologist

Not sure where to begin?

One conversation with a gemologist replaces a hundred open tabs. We will guide you the way we would guide a close friend.

John Anderson · Lead Gemologist · (800) 779-1726

Book a Consultation

3 Carat Lab Grown Diamond Rings

A true statement diamond. A lab grown diamond puts three carats within reach without compromising on certification or beauty. Every ring on this page is a Select ring: the IGI certified diamond is already matched to the setting and included in the price, made to order in our Los Angeles atelier in platinum or solid gold.

One fair price, complimentary insured U.S. shipping, and a lifetime warranty against manufacturing defects.

3 Carat

3 Carat Lab Grown Diamond Rings

The rings on this page are complete: an IGI certified lab diamond already set, with 3 carat as one of the carat weights you can choose on the ring page. A 3 carat round measures about 9.3 mm across; the same weight spreads to about 11.5 × 8 as an oval and 9.5 × 7.5 as an emerald cut, because carat is weight, not size.

Every ring is made to order in our Los Angeles atelier, modeled around the exact measurements of the diamond before it is made. If you would rather a natural diamond, the same settings are built around a GIA certified 3 carat diamond through the configurator, where you choose the diamond first.

9.3 mm
Round
11.5 × 8
Oval
8 × 8
Cushion
9.5 × 7.5
Emerald
12 × 8
Pear

One fair price

The ring page shows one price for the complete ring at each carat weight. No codes, no strikethroughs, no timing the purchase.

IGI and GIA certified

Lab diamonds graded by IGI, natural diamonds graded by GIA. Our gemologist verifies every diamond against its certificate before it is set.

Resizing and warranty

60 day complimentary resizing, lifetime warranty, and the Ring Size Guide before you order.

Two ways to own one

Choose a complete ring below. Pick the design, the metal and the carat weight on the ring page. The lab diamond is already matched to the setting.

Build it around a natural diamond. Choose a GIA certified 3 carat diamond from our inventory, with a ROSI™ Score Report on any diamond you are considering, and John Anderson, our Lead Gemologist, reviews the shortlist with you before the setting is modeled to it.

All Select Rings Build Your Ring

Two 3 carat diamonds with the same certificate can look like different diamonds on the hand. Cut is where the difference lives, and it is the one grade worth paying for. Color and clarity above what the eye can see are paid for and never seen.

Talk to a jeweler before you decide

John Anderson, our Lead Gemologist, compares the candidates with you on the phone or by video. Call 1-800-779-1726 or request a consultation. There is no charge and no obligation.

Frequently Asked Questions

How big is a 3 carat diamond?

A well cut 3 carat round measures about 9.3 mm across, an oval about 11.5 × 8, a cushion about 8 × 8, an emerald cut about 9.5 × 7.5, a pear about 12 × 8. Carat is weight, so the exact measurements for any diamond are on its certificate.

Are the rings on this page natural or lab diamonds?

The complete rings shown here are IGI certified lab diamond rings, with 3 carat as one of the carat weights you can choose. The same settings are made around a GIA certified natural 3 carat diamond through our configurator, where you choose the diamond first and the setting is modeled to it.

Which grades should I choose at 3 carat?

Cut first: Excellent on the certificate for a round, or a reviewed cut for a fancy shape. G color or better in platinum and white gold, H or better in yellow and rose gold. VS2 or better clarity. Higher color and clarity grades than these are not visible on the hand.

How long does a 3 carat diamond ring take to make?

8 to 12 business days from the day the diamond is confirmed. The CAD model is built around the measurements on the certificate, the diamond is verified against the certificate by our gemologist, and the ring is finished and inspected in Los Angeles before it ships insured.