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18 Carat Diamond

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18 Karat Rose Gold Star Diamond Neckalce 2/5 Carat
Located in San Francisco, CA
This elegant necklace features 7 diamond stars Micro Prong-set linked to each other via delicate
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Star Diamond Neckalce 2/5 Carat
Located in San Francisco, CA
This elegant necklace features 7 diamond stars Micro Prong-set linked to each other via delicate
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, White Gold

2.18 Carat Yellow Sapphire Diamond 18 Karat White Gold Band
By Roshe Jewels
Located in Los Angeles, CA
Diamonds that weigh 0.91 Carats. The diamonds have a clarity of VS and color of H. The Total Carat Weight
Category

21st Century and Contemporary American Contemporary Band Rings

Materials

Yellow Sapphire, Diamond, White Gold, 18k Gold

18 Karat Yellow Gold Spear Diamond Necklace 1/4 Carat
Located in San Francisco, CA
This elegant necklace features 100 brilliants diamond micro-prong set in 5 spear-shaped pendants
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Spear Diamond Necklace 1/4 Carat
Located in San Francisco, CA
This elegant necklace features 100 brilliants diamond micro-prong set in 5 spear-shaped pendants
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Rose Gold

18 Karat Rose Gold Triangle Diamond Necklace 1/2 Carat
Located in San Francisco, CA
This elegant necklace features 135 brilliants diamond micro-prong set in 11 Triangle-shaped
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Triangle Diamond Necklace 1/2 Carat
Located in San Francisco, CA
This elegant necklace features 135 brilliants diamond micro-prong set in 11 Triangle-shaped
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, White Gold

18 Karat Yellow Gold Triangle Diamond Necklace 1/2 Carat
Located in San Francisco, CA
This elegant necklace features 135 brilliants diamond micro-prong set in 11 Triangle-shaped
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Yellow Gold

Diamonds Sardinian Coral 18 Carat White Gold Brooch
By SCALA GIOIELLI
Located in Marcianise, IT
High Jewelry Masterpiece: Diamond-Paved Lobster Brooch on Sardinian Red Coral Presenting an
Category

Early 2000s Italian Artisan Brooches

Materials

Coral, Diamond, 18k Gold, White Gold

18 Karat Rose Gold Floral Diamond Necklace 1/5 Carat
Located in San Francisco, CA
This delicate and elegant necklace features round brilliant diamonds micro-prong set in a floral
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Floral Diamond Necklace 1/5 Carat
Located in San Francisco, CA
This delicate and elegant necklace features round brilliant diamonds micro-prong set in a floral
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, White Gold

18 Karat Yellow Gold Floral Diamond Necklace 1/5 Carat
Located in San Francisco, CA
This delicate and elegant necklace features round brilliant diamonds micro-prong set in a floral
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Yellow Gold

18 Karat Yellow Gold Hoop Diamond Earrings 1/2 Carat
Located in San Francisco, CA
This hoop earring features one row of round brilliant diamonds micro-prong set. It is 3/4 of an
Category

21st Century and Contemporary American Hoop Earrings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Hoop Diamond Earrings 1/2 Carat
Located in San Francisco, CA
This hoop earring features one row of round brilliant diamonds micro-prong set. It is 3/4 of an
Category

21st Century and Contemporary American Hoop Earrings

Materials

Diamond, Rose Gold

18 Karat White Gold Hoop Diamond Earrings 1/2 Carat
Located in San Francisco, CA
This hoop earring features one row of round brilliant diamonds micro-prong set. It is 3/4 of an
Category

21st Century and Contemporary American Hoop Earrings

Materials

Diamond, White Gold

Modern 18 Karat Gold 3.55 Carat Emerald 4.30 Carat Diamond Bracelet
Located in Vilnius, Vilniaus apskr.
/4, P1) - 18 diamonds (round brilliant cut, TW 2.00ct, RW+/RW, VS-SI) - 20 diamonds (marquise cut, TW
Category

21st Century and Contemporary Modern Link Bracelets

Materials

Diamond, Emerald, Gold, 18k Gold

Natural Diamond 1.20 carats 18 Karat White Gold Cocktail Ring
Located in Antwerpen, BE
Weight: 6.26 grams Gemstone: Natural Diamonds Shape: Round Brilliant/ Baguette Total Carat Weight: 1.20
Category

2010s Belgian Modern Engagement Rings

Materials

Diamond, White Gold, 18k Gold, Gold

Ruby Necklace Choker in 18 Carat 18 Karat Gold 60 Rubies 25 Carats and Diamonds
Located in Paris, FR
Ruby and diamond line necklace Choker in 18 carat white gold setting. It is composed of 60 rubies
Category

Early 2000s French More Necklaces

Materials

Diamond, Ruby, Gold, 18k Gold, White Gold, Yellow Gold

Diamonds Stud Earrings 18 Carat White Gold Set with 1.86 Carats of Diamonds
Located in Paris, FR
Pair of 18 kt white gold stud earrings each set with a diamond of approximately 0.9 kt. Total
Category

Early 2000s Italian Stud Earrings

Materials

Diamond, 18k Gold, White Gold

18 Karat White Gold Marquise Diamond Necklace 1/3 Carat
Located in San Francisco, CA
This delicate and elegant necklace features round brilliant diamonds micro-prong set in seven (7
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, White Gold

18 Karat Yellow Gold Marquise Diamond Necklace 1/3 Carat
Located in San Francisco, CA
This delicate and elegant necklace features round brilliant diamonds micro-prong set in seven (7
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Marquise Diamond Necklace 1/3 Carat
Located in San Francisco, CA
This delicate and elegant necklace features round brilliant diamonds micro-prong set in seven (7
Category

21st Century and Contemporary American More Necklaces

Materials

Diamond, Rose Gold

1.60 Carat diamond full eternity diamond ring gold 18 Karat
Located in Uccle, BE
Full eternity diamond ring. 18 Karat white gold ring set with 26 brilliant diamonds for a total
Category

21st Century and Contemporary European Modern Band Rings

Materials

Diamond, Gold, 18k Gold

Earrings Diamonds and Pearl Pink Gold 18 Carat
Located in Vannes, FR
Earrings Diamonds and Cultured Pearl Pink Gold 18 Carats Discover these magnificent earrings in
Category

21st Century and Contemporary French Baroque Drop Earrings

Materials

Diamond, Pearl, Cultured Pearl, Freshwater Pearl, Gold, 18k Gold, Rose Gold

Natural 15.50 Carat Graduated Diamond Riviera Tennis Necklace in Platinum 18"
By Gad Co.
Located in Miami, FL
15.50 Carat Total Natural Graduated Diamond Riviera Necklace in Platinum. This unisex necklace
Category

21st Century and Contemporary North American Modern Pendant Necklaces

Materials

Diamond, Platinum

Choco Moonstone Peridoto Diamonds Rose Gold 18 Carats
Located in Vannes, FR
Choco Moonstone Peridoto Diamonds Rose Gold 18 Carats Discover Timeless Elegance with These
Category

21st Century and Contemporary French Art Deco Dangle Earrings

Materials

Diamond, Moonstone, Peridot, Gold, 18k Gold, Yellow Gold

Diamonds Coral 18 Carat White Gold Dangle Earrings
By SCALA GIOIELLI
Located in Marcianise, IT
Angel Skin Pink Coral & Diamond Dangle Earrings Indulge in refined elegance with these exquisite
Category

Early 2000s Italian Artisan Dangle Earrings

Materials

Coral, Diamond, 18k Gold, White Gold

40 Carat Natural Fancy Multicolored Diamond Bead Necklace in 18 Karat
By MOGULDIAM INC
Located in New York, NY
Simply elegant necklace featuring sparkling faceted multicolored diamond beads ( with green, pink
Category

Early 2000s American Contemporary Beaded Necklaces

Materials

Diamond, 18k Gold

1.8 Carat Diamond Flower/Cluster Stud Earring 18 Karat White Gold
Located in New York, NY
A fabulous pair of earrings with an enormous amount of look and sparkle! 1.8 carats diamonds set in
Category

2010s Stud Earrings

Materials

Diamond, 18k Gold

27 carat Amethyst Diamond ring in 18 KT white gold
Located in Palm Desert, CA
Set in 18 karat white gold, weighing 28 grams, is one Emerald Cut 27 carat Amethyst with 8 Round
Category

21st Century and Contemporary North American Fashion Rings

Materials

Amethyst, Diamond, 18k Gold, White Gold

Tennis Bracelet 18-Carat White Gold Set with Diamonds for 4 Carat
Located in SAINT-OUEN-SUR-SEINE, FR
Superb bracelet in 18 carat white gold, line of diamonds set for 4 carats in total color / G and
Category

1990s French Contemporary Tennis Bracelets

Materials

Diamond, White Gold

18 Karat White Gold 13.50 Carat Diamond Bracelet
By Diana M. Jewels
Located in New York, NY
18K White gold, tri row diamond bracelet, features 13.50 Carats of white round brilliant cut
Category

21st Century and Contemporary American Link Bracelets

Materials

Diamond, Yellow Diamond, 18k Gold, White Gold

5.20 Carat Colombian Emerald Sapphire Diamond Dangle Earrings 18 Karat
By Emeralds Maravellous
Located in US
sapphires 1.72 carat total weight. The gemstones are accented with 0.48-carat round brilliant-cut diamonds
Category

21st Century and Contemporary American Contemporary Dangle Earrings

Materials

Diamond, Emerald, Sapphire, Pink Sapphire, 18k Gold, Yellow Gold

8.65 Carat Diamond 18 Karat Gold Bombe Ring
By Meghna Jewels
Located in Hoffman Estate, IL
This stunning ring is crafted from 18-karat gold. It is set with 4.0 carats champagne and 4.65 of
Category

21st Century and Contemporary Unknown Contemporary Cocktail Rings

Materials

Diamond, Brown Diamond, Gold, 18k Gold, White Gold

2.27 Carat Princess Cut / Baguette Diamond 18 Karat Gents Ring
By Sebastian Bernard
Located in Los Angeles, CA
perfectly matched 2.5 mm princess cut and 6 pieces of straight Baguette Diamonds(Total Weight 2.12 Ct
Category

2010s American Bridal Rings

Materials

Diamond, 18k Gold

2.12 Carat Princess Cut / Baguette Diamond 18 Karat Gents Ring
By Sebastian Bernard
Located in Los Angeles, CA
perfectly matched 2.4 mm princess cut and 7 pieces of straight Baguette Diamonds(Total Weight 2.12 Ct
Category

2010s American Bridal Rings

Materials

Diamond, 18k Gold

White Gold Stack 18 Carat Band Ring Diamonds
By SCALA GIOIELLI
Located in Marcianise, IT
18-karat white gold band rings with diamonds, entirely handmade by expert Italian goldsmiths
Category

1990s Artisan Band Rings

Materials

Diamond, 18k Gold, White Gold

Natural Diamond 0.33 Carats 18 Karats Yellow Gold Hoop Huggie Earrings
Located in Antwerpen, BE
Graduated Diamond Huggie Hoop Earrings in 18 Karat Yellow Gold, 0.33 Carats Refined yet radiant
Category

2010s Belgian Modern Hoop Earrings

Materials

Diamond, 18k Gold, Yellow Gold

0.80 Carat Invisible/Channel Set Diamond 18 Karat Gents Ring
By Sebastian Bernard
Located in Los Angeles, CA
Round set in two clusters around a cluster of 4 pieces of 2.5 mm Invisible Set Princess Cut Diamonds
Category

2010s American Band Rings

Materials

Diamond, 18k Gold

Tacori Princess Cut Diamond Engagement Ring 18 Carat White Gold
By Tacori
Located in Chicago, IL
TACORI Princess Diamond Engagement Ring Model 28095 in 18k White Gold. The ring weighs 7.6
Category

2010s Italian Modern Band Rings

Materials

Diamond, White Gold

Art Deco Diamond 18 Carat White Gold Bracelet
Located in Chipping Campden, GB
This bracelet is modelled in 18carat white gold. The diamond total of this bracelet is approx
Category

Vintage 1910s British Art Deco Link Bracelets

Materials

Diamond, Gold, White Gold

Diamond and 18 Carat Yellow Gold Hamsa Hand Pendant
By Tobi Gem Setting
Located in London, GB
Finely crafted from solid 18 carat yellow gold, this Hamsa hand pendant features a clean
Category

1990s English Modern Pendant Necklaces

Materials

Diamond, White Diamond, Gold, 18k Gold, Yellow Gold

1.42ct Sapphire and Diamond 18 Carat White Gold Engagement Ring
By Tobi Gem Setting
Located in London, GB
set 18 carat white gold mount tapering to a fine solid shank at the back. The ring in inlaid with a
Category

2010s English Modern Engagement Rings

Materials

Diamond, Sapphire, 18k Gold, White Gold

9.48 Carat Diamond Earring In 18 Karat White Gold
By Rewa Jewellery
Located in Bangkok, TH
gold. Studded with 18 pieces of pear shapped diamonds weighing approximately 7.10 carat and 8 heart
Category

2010s Thai Aesthetic Movement Chandelier Earrings

Materials

Diamond, 18k Gold, White Gold

Diamond Earrings in 18 Carat White Gold 4 Carats of Diamonds Knot Pattern
Located in Paris, FR
Exceptional Pair of 18 kt white gold earrings with a knot pattern, each retaining a large bezel-set
Category

Early 2000s Unknown Chandelier Earrings

Materials

Diamond, 18k Gold, White Gold

18 Karat Rose Gold Turin Diamond Ring 1/10 Carat
Located in San Francisco, CA
This ring features a perfectly matched round brilliant diamonds Pave set. Experience the difference
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Turin Diamond Ring 1/10 Carat
Located in San Francisco, CA
This ring features a perfectly matched round brilliant diamonds Pave set. Experience the difference
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat White Gold Turin Diamond Ring 1/10 Carat
Located in San Francisco, CA
This ring features a perfectly matched round brilliant diamonds Pave set. Experience the difference
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

Earrings Yellow Gold 18 Carat with Natural Diamonds 0.20 Carat single cut
Located in Heemstede, NL
beautifully crafted, showcasing timeless beauty. Material: 18 carat yellow gold Gemstones: natural diamonds
Category

Vintage 1980s Belgian Hoop Earrings

Materials

Diamond, 18k Gold, Yellow Gold

12.50 Carat Sapphire 1.00 Carat Diamond 18 Karat Yellow Gold Bangle Bracelet
Located in New York, NY
Diamond 18 Karat Yellow Gold Bangle Bracelet Style: Bangle Metal: 18 Karat Yellow Gold Gemstone 1: 1 Carat
Category

20th Century Bangles

Materials

Diamond, Sapphire, 18k Gold

10.40 Carats Sapphires 0.30 Carats White Diamonds 18 Karats Gold Chain Necklace
By Rossella Ugolini
Located in Rome, IT
Rossella Ugolini, 10.40 Carats Sapphires 0.30 Carats White Diamonds 18 Karats Gold Blue Necklace
Category

2010s Italian Art Deco Chain Necklaces

Materials

Diamond, Sapphire, White Diamond, Yellow Gold, White Gold, 18k Gold, Gold

18 Karat White Gold Orchid Diamond Cluster Ring 1 Carat
Located in San Francisco, CA
This sparkling band features round brilliant diamonds set in gleaming shared prongs. Experience the
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

18 Karat White Gold Briana Diamond Ring 1/3 Carat
Located in San Francisco, CA
A delicate Shared prong diamonds wedding band for a sparkling look. Experience the difference
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

18 Karat Yellow Gold Briana Diamond Ring 1/3 Carat
Located in San Francisco, CA
A delicate Shared prong diamonds wedding band for a sparkling look. Experience the difference
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Briana Diamond Ring 1/3 Carat
Located in San Francisco, CA
A delicate Shared prong diamonds wedding band for a sparkling look. Experience the difference
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Orchid Diamond Cluster Ring 1 Carat
Located in San Francisco, CA
This sparkling band features round brilliant diamonds set in gleaming shared prongs. Experience the
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Orchid Diamond Cluster Ring 1 Carat
Located in San Francisco, CA
This sparkling band features round brilliant diamonds set in gleaming shared prongs. Experience the
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

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18 Carat Diamond For Sale on 1stDibs

On 1stDibs, you can find the most appropriate 18 carat diamond for your needs in our varied inventory. Every item for sale was constructed with extraordinary care, often using Gold, 18k Gold and White Gold. Our collection of these items for sale includes 16174 vintage editions and 32669 modern creations to choose from as well. Finding the perfect 18 carat diamond may mean sifting through those created during different time periods — you can find an early version that dates to the 18th Century and a newer variation that were made as recently as the 21st Century. For this particular accessory, there are many different carat weights to choose from, but .5 Carat and 1 Carat versions are of considerable interest. Finding an appealing 18 carat diamond — no matter the origin — is easy, but Roman Malakov, Meghna Jewels and LB Exclusive each produced a popular version that is worth a look. A round cut version of this piece has appeal, but there are also oval cut and cushion cut versions for sale. If you’re browsing our inventory for a 18 carat diamond, you’ll find that many are available today for women, but there are still pieces to choose from for unisex and men.

How Much is a 18 Carat Diamond?

Prices for a 18 carat diamond can differ depending upon size, time period and other attributes — at 1stDibs, these accessories begin at $19 and can go as high as $135,979,328, while this accessory, on average, fetches $5,813.

Why Gold Shines in Jewelry Craftsmanship

Gold is the feel-good metal, the serotonin of jewelry. Wear vintage and antique gold necklaces, watches, gold bracelets or gold rings and you feel happy, you feel dressed, you feel, well, yourself. 

Gold, especially yellow gold, with its rich patina and ancient pedigree going back thousands of years, is the steady standby, the well-mannered metal of choice. Any discussion of this lustrous metal comes down to a basic truth: Gold is elementary, my dear. Gold jewelry that couples the mystique of the metal with superb design and craftsmanship achieves the status of an enduring classic. Many luxury houses have given us some of our most treasured and lasting examples of gold jewelry over the years.

Since its founding, in 1837, Tiffany Co. has built its reputation on its company jewelry as well as its coterie of boutique designers, which has included Jean Schlumberger, Donald Claflin, Angela Cummings and Elsa Peretti. There are numerous gold Tiffany classics worth citing. Some are accented with gemstones, but all stand out for their design and the workmanship displayed.

For the woman who prefers a minimalist look, the Tiffany Co. twist bangle (thin, slightly ovoid) is stylishly simple. For Cummings devotees, signature pieces feature hard stone inlay, such as her pairs of gold ear clips inlaid with black jade (a play on the classic Chanel black and tan), or bangles whose design recalls ocean waves, with undulating lines of lapis lazuli and mother-of-pearl. And just about any design by the great Jean Schlumberger is by definition a classic.

Even had he eschewed stones and diamonds, Southern-born David Webb would be hailed for the vast arsenal of heavy gold jewelry he designed. Gold, usually hammered or textured in some manner, defines great David Webb jewelry. The self-taught jeweler made very au courant pieces while drawing inspiration from ancient and out-of-the-way sources — East meets West in the commanding gold necklaces made by Webb in the early 1970s. The same could be said for his endlessly varied gold cuffs.

In Europe, many houses have given us gold jewelry that sets the highest standard for excellence, pieces that were highly sought after when they were made and continue to be so. 

Numerous designs from Cartier are homages to gold. There are the classic Trinity rings, necklaces and bracelets — trifectas of yellow, white and rose gold. As a testament to the power of love, consider the endurance of the Cartier Love bracelet.

Aldo Cipullo, Cartier’s top in-house designer from the late 1960s into the early ’70s, made history in 1969 with the Love bracelet. Cipullo frequently said that the Love bracelet was born of a sleepless night contemplating a love affair gone wrong and his realization that “the only remnants he possessed of the romance were memories.” He distilled the urge to keep a loved one close into a slim 18-karat gold bangle. 

BVLGARI and its coin jewelry, gemme nummarie, hit the jackpot when the line launched in the 1960s. The line has been perennially popular. BVLGARI coin jewelry features ancient Greek and Roman coins embedded in striking gold mounts, usually hung on thick link necklaces of varying lengths. In the 1970s, BVLGARI introduced the Tubogas line, most often made in yellow gold. The Tubogas watches are classics, and then there is the Serpenti, the house's outstanding snake-themed watches and bracelets.

A collection called Monete that incorporated the gold coins is one of several iconic BVLGARI lines that debuted in the 1970s and ’80s, catering to a new generation of empowered women. Just as designers like Halston and Yves Saint Laurent were popularizing fuss-free ready-to-wear fashion for women on the go, BVLGARI offered jewels to be lived in

Since Van Cleef Arpels opened its Place Vendôme doors in 1906, collection after collection of jewelry classics have enchanted the public. As predominantly expressed in a honeycomb of gold, there is the Ludo watch and accessories, circa the 1920s, and the golden Zip necklace, 1951, whose ingenious transformation of the traditional zipper was originally proposed by the Duchess of Windsor. Van Cleef's Alhambra, with its Moroccan motif, was introduced in 1968 and from the start its popularity pivoted on royalty and celebrity status. It remains one of VCA’s most popular and collected styles.

Mention must be made of Buccellati, whose name is synonymous with gold so finely spun that it suggests tapestry. The house’s many gold bracelets, typically embellished with a few or many diamonds, signified taste and distinction and are always in favor on the secondary market. Other important mid-20th-century houses known for their gold-themed jewelry include Hermès and Ilias Lalaounis.

Find a stunning collection of vintage and antique gold jewelry on 1stDibs.

The Legacy of Diamond in Jewelry Design

Antique diamond rings, diamond tiaras and dazzling vintage diamond earrings are on the wish lists of every lover of fine jewelry. And diamonds and diamond jewelry are primarily associated with storybook engagements and red-carpet grand entrances — indeed, this ultra-cherished gemstone has a dramatic history on its hands.

From “A Diamond Is Forever” to “Diamonds Are a Girl’s Best Friend,” pop culture has ingrained in our minds that diamonds are the most desired, the most lasting and the most valuable gemstone. But what makes the diamond so special? Each stone — whether it’s rubies, sapphires or another stone — is unique and important in its own right. April babies might claim diamonds for themselves, but just about everyone wants this kind of sparkle in their lives!

There are several factors that set diamonds apart from other stones, and these points are important to our gem education.

Diamonds are minerals. They are made up of almost entirely of carbon (carbon comprises 99.95 percent; the remainder consists of various trace elements). Diamonds are the hardest gemstones, ranking number 10 on the Mohs Hardness Scale. Even its name, diamond, is rooted in the Greek adamas, or unconquerable. The only object that can scratch a diamond is another diamond. Diamonds are formed deep within the earth at very high temperatures (1,652–2,372 degrees Fahrenheit at depths between 90 and 120 miles beneath the earth’s surface) and are carried up by volcanic activity. Diamonds are quite rare, according to the Gemological Institute of America, and only 30 percent of all the diamonds mined in the world are gem quality.

In the 1950s, the Gemological Institute of America developed the 4Cs grading system to classify diamonds: clarity, color, cut and carat weight. Not all diamonds are created equal (there are diamonds, and then there are diamonds). The value of the diamond depends on the clarity (flawless diamonds are very rare but a diamond's value decreases if there are many blemishes or inclusions), color (the less color the higher the grade), cut (how the diamond’s facets catch the light, certain cuts of diamonds show off the stone better than others) and carat weight (the bigger, the better).

When you start shopping for a diamond engagement ring, always prioritize the cut, which plays the largest role in the diamond's beauty (taking the time to clean your diamond ring at least every six months or so plays a role in maintaining said beauty). And on 1stDibs, a range of buying guides can be found for those in the market for antique engagement ringsvintage engagement rings or Art Deco engagement rings

Shop antique and vintage diamond rings, diamond necklaces and other extraordinary diamond jewelry on 1stDibs.  

Questions About 18 Carat Diamond
  • 1stDibs ExpertMarch 22, 2022
    A 24-carat diamond is a precious diamond gemstone that weighs 24 carats. One carat weighs 200 milligrams, meaning a 24-carat diamond weighs roughly 4.8 grams. That equates to roughly 0.17 ounces. On 1stDibs, shop a variety of diamond jewelry.
  • 1stDibs ExpertApril 5, 2022
    Yes, there are three-carat diamonds, and you can find them from a number of different jewelers and other retailers. Find an assortment of diamond jewelry from the world’s top sellers on 1stDibs.
  • 1stDibs ExpertNovember 6, 2023
    There is no hard-and-fast rule for how many carats a diamond necklace should be. On average, solitaire diamond necklaces range from 0.5 to 1 carat, but you can find pieces with larger and smaller stones. Tennis chains that feature continuous diamonds set into links usually have much higher total carat weights. For example, one might feature 60 individual diamonds, each 0.20 carats in size, for a total carat weight of 12.0 carats. Shop a wide range of diamond necklaces on 1stDibs.
  • 1stDibs ExpertApril 5, 2022
    A nine-carat diamond is considered rare and holds a premium price. Because of their rarity and size, nine-carat diamonds are a coveted choice for engagement rings. One of the most famous nine-carat diamond rings belongs to actress Kate Hudson, who has a nine-carat emerald cut diamond complemented with tapered baguettes on a platinum band. Shop a selection of diamond jewelry on 1stDibs.
  • 1stDibs ExpertSeptember 28, 2021
    An 8-carat diamond’s worth varies depending on the 4Cs of diamond quality – color, cut, clarity and carat. On an average an 8-carat diamond could cost you between $17,500 to $90,000. It is also likely that the price range per carat will be even broader. On 1stDibs, you can find a variety of 8-carat diamond jewelry from different periods and styles to choose from.
  • 1stDibs ExpertSeptember 28, 2021
    A 4-carat diamond’s worth varies depending on the 4Cs of diamond quality – color, cut, clarity and carat. On average, a 4-carat diamond could cost you between $8,400 to $71,500. It is also likely that the price range per carat will be even broader. On 1stDibs, you can find a variety of 4-carat diamond jewelry.
  • 1stDibs ExpertSeptember 28, 2021
    A 6-carat diamond’s worth varies depending on the 4Cs of diamond quality – color, cut, clarity and carat. On average, a 6-carat diamond could cost you between $15,000 to $80,000. It is also likely that the price range per carat will be even broader. On 1stDibs, you can find a variety of 6-carat diamond jewelry.
  • 1stDibs ExpertSeptember 28, 2021
    A 5-carat diamond’s worth varies depending on the 4Cs of diamond quality – color, cut, clarity and carat. On average, a 5-carat diamond could cost you between $9,600 to $67,500. It is also likely that the price range per carat will be even broader. On 1stDibs, you can find a variety of 5-carat diamond jewelry.
  • 1stDibs ExpertSeptember 28, 2021
    The minimum value of a 25-carat diamond ranges from $300 to $1,400. The prices change subject to the fluctuation of market factors. The value is defined based on the 4Cs — color, clarity, cut and carat weight. Shop antique, vintage and new diamond jewelry on 1stDibs.
  • 1stDibs ExpertFebruary 27, 2024
    Whether a 1.5-carat diamond is too big depends on the type of jewelry in question and your personal preferences. A single stud earring that is 1.5 carats is rather large and would cover the entire earlobe. In terms of rings, a 1.5-carat diamond is larger than average. Find a variety of diamond jewelry on 1stDibs.
  • 1stDibs ExpertFebruary 13, 2023
    Yes, a two-carat diamond is generally rarer than a smaller diamond, especially high-quality two-carat diamonds. When larger diamonds are found in nature, they usually have flaws. And prices per carat don’t increase as weight increases. A three-carat gem can be less valuable than a one-carat stone, for example, if all of the other attributes are of lesser quality in the larger diamond. Shop an assortment of diamond jewelry from some of the world’s top jewelers on 1stDibs.
  • 1stDibs ExpertFebruary 27, 2024
    In terms of dimensions, how large a 3-carat diamond is varies. The shape of the diamond will determine its length and width. Weighing 600 milligrams, diamonds that are 3 carats are generally considered to be large stones. On 1stDibs, shop a large collection of diamond jewelry from some of the world's top dealers.
  • 1stDibs ExpertFebruary 22, 2021
    The size of a 12 carat diamond is dependent on diamond cut. A 12 carat round diamond is roughly 15 mm in size.
  • 1stDibs ExpertSeptember 28, 2021
    A 9-carat diamond’s worth varies depending on the 4Cs of diamond quality — color, cut, clarity and carat. On average, a 9-carat diamond could cost you between $19,000 to $1,000,000. It is also likely that the price range per carat will be even broader. On 1stDibs, you can find a variety of 9-carat diamond jewelry from different periods and styles to choose from.
  • 1stDibs ExpertFebruary 22, 2021
    Depending on the quality, age, and designer, a 1-carat diamond can cost between $1,300 and $16,500.
  • 1stDibs ExpertAugust 17, 2021
    A 7-carat diamond can cost anywhere between $12,000 and $185,000 depending on the quality of the stone. The fewer imperfections, the more expensive the diamond. Some 7-carat diamonds can cost more than $400,000.
  • 1stDibs ExpertSeptember 28, 2021
    A 3-carat diamond’s worth varies depending on the 4Cs of diamond quality – color, cut, clarity and carat. On average, a 3-carat diamond could cost you between $7,200 to $51,000. It is also likely that the price range per carat will be even broader. On 1stDibs, you can find a variety of 3-carat diamond jewelry today.
  • 1stDibs ExpertAugust 24, 2021
    A 2 carat oval diamond is approximately 10.23mm × 6.82mm × 4.16mm in size. These diamonds usually have an approximate face-up area of 57.21 mm². Find a variety of diamonds on 1stDibs.
  • 1stDibs ExpertNovember 2, 2023
    There is no rule for how many carats a diamond wedding ring should be. You're free to choose a ring with a carat weight that appeals to you and fits your budget. The average carat weight for diamond wedding rings is 1 to 1.9 carats. Shop an assortment of diamond wedding rings on 1stDibs.
  • 1stDibs ExpertAugust 17, 2021
    A 7-carat diamond can cost anywhere between $12,000 and $185,000 depending on the quality of the stone. The fewer imperfections, the more expensive the diamond. Some 7-carat diamonds can cost more than $400,000.