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18 Carat Diamond

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18 Karat White Gold Entwine Diamond Ring 1/10 Carat
Located in San Francisco, CA
diamonds. Experience the difference! Product details: Center Gemstone Color: WHITE Side Gemstone Type
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

18 Karat White Gold Vega Fashion Diamond Ring 1 Carat
Located in San Francisco, CA
This stunning ring features round brilliant diamonds micro-prong-set in three-row. Experience the
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

18 Karat Rose Gold Entwine Diamond Ring 1/10 Carat
Located in San Francisco, CA
diamonds. Experience the difference! Product details: Center Gemstone Color: WHITE Side Gemstone Type
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Vega Fashion Diamond Ring 1 Carat
Located in San Francisco, CA
This stunning ring features round brilliant diamonds micro-prong-set in three-row. Experience the
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Yellow Gold Camila Diamond Ring 1/6 Carat
Located in San Francisco, CA
This victorian style ring features 15 round brilliant diamonds prong-set in 5 channel boxes
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Camila Diamond Ring 1/6 Carat
Located in San Francisco, CA
This victorian style ring features 15 round brilliant diamonds prong-set in 5 channel boxes
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Entwine Diamond Ring 1/10 Carat
Located in San Francisco, CA
diamonds. Experience the difference! Product details: Center Gemstone Color: WHITE Side Gemstone Type
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Vega Fashion Diamond Ring 1 Carat
Located in San Francisco, CA
This stunning ring features round brilliant diamonds micro-prong-set in three-row. Experience the
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat White Gold Camila Diamond Ring 1/6 Carat
Located in San Francisco, CA
This victorian style ring features 15 round brilliant diamonds prong-set in 5 channel boxes
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

18 Karat White Gold Merida Diamond Ring 1/4 Carat
Located in San Francisco, CA
This curve ring features sparkling micro - prong - set diamonds along the top of this delicate band
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

18 Karat Rose Gold Merida Diamond Ring 1/4 Carat
Located in San Francisco, CA
This curve ring features sparkling micro - prong - set diamonds along the top of this delicate band
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Nati Diamond Ring 1/4 Carat
Located in San Francisco, CA
This petite curved band features Micro -Prongs set round brilliant diamonds to match your
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Yellow Gold Merida Diamond Ring 1/4 Carat
Located in San Francisco, CA
This curve ring features sparkling micro - prong - set diamonds along the top of this delicate band
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Nati Diamond Ring 1/4 Carat
Located in San Francisco, CA
This petite curved band features Micro -Prongs set round brilliant diamonds to match your
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat White Gold Nati Diamond Ring 1/4 Carat
Located in San Francisco, CA
This petite curved band features Micro -Prongs set round brilliant diamonds to match your
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

22.00 Carat Aquamarine and Diamond 18 Carat White Gold Cocktail Ring
Located in London, GB
This spectacular 18 carat white gold cocktail ring is beautifully set with an emerald cut
Category

2010s Modern Cocktail Rings

Materials

Aquamarine, Diamond, Gold, 18k Gold, White Gold

14.93 Carat Diamond Bracelet in 18 Karat White Gold
By Rewa Jewellery
Located in Bangkok, TH
Elegance personified in this exquisite diamond bracelet designed by Rewa jewels in 18 karat white
Category

2010s Thai Modern Cuff Bracelets

Materials

Diamond, White Gold

Vintage Sapphire and Diamond 18 Carat Gold Cluster Ring
Located in Chipping Campden, GB
This striking sapphire and diamond cluster ring is modelled in 18 Carat Gold and the stones are set
Category

Vintage 1960s Unknown Cluster Rings

Materials

Diamond, Sapphire, Gold, Platinum

18 Karat Yellow Gold Noga Diamond Band 1/5 Carat
Located in San Francisco, CA
This curve ring features sparkling micro - prong - set diamonds along the top of this delicate band
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Noga Diamond Band 1/5 Carat
Located in San Francisco, CA
This curve ring features sparkling micro - prong - set diamonds along the top of this delicate band
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Rose Gold

18 Karat White Gold Noga Diamond Band 1/5 Carat
Located in San Francisco, CA
This curve ring features sparkling micro - prong - set diamonds along the top of this delicate band
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, White Gold

Ruby and Diamond 18 Carat Gold Cluster Ring
Located in Chipping Campden, GB
. Either side of the central diamond air a smaller 10pt diamond. The ring is modelled in 18 carat gold
Category

Vintage 1960s British Cluster Rings

Materials

Diamond, Ruby, Gold

4.55 Carat Colombian Emerald Tanzanite and Diamond Dangle Earrings 18 Karat
By Emeralds Maravellous
Located in US
4.55 Carat Colombian Emerald Tanzanite and Diamond Drop Dangle Earrings 18K This ELEGANT pair of
Category

2010s American Contemporary Drop Earrings

Materials

Diamond, White Diamond, Emerald, Tanzanite, 18k Gold, Yellow Gold

18 Karat Yellow Gold Cushion Yellow Diamonds Eternity Ring 4. Carat
Located in San Francisco, CA
This Eternity Ring showcase perfectly matched 20 Oval shape Natural Yellow Diamonds in a total
Category

21st Century and Contemporary American Band Rings

Materials

Diamond, Yellow Diamond, Yellow Gold

Edwardian Diamond and 18 Carat Double Cluster Ring
Located in Chipping Campden, GB
This wonderful double diamond cluster holds sparkling diamonds measuring 4pts each at the centre
Category

Antique Early 1900s British Edwardian More Rings

Materials

Diamond, 18k Gold, Platinum

18 Karat Gold 2.22 Carat Diamond Drop Earrings
By Gems Paradise
Located in Jaipur, IN
18 Karat Gold 2.22 Carat Diamond Drop Earrings You are a beauty. Classic, Modern and
Category

2010s Indian Contemporary Dangle Earrings

Materials

Diamond, Gold, 18k Gold

PANIM 6.79 Carat Diamond Briolette 18 Karat Yellow Gold Choker Necklace
By PANIM
Located in Tsim Sha Tsui, Hong Kong
PANIM 6.79 Carat Diamond Briolette 18 Karat Yellow Gold Choker Necklace A diamond briolette choker
Category

21st Century and Contemporary Indian Modern Chain Necklaces

Materials

Diamond, White Diamond, 18k Gold, Yellow Gold

2.65 Carat Diamond/1.15 Carat Blue Sapphire 18 Karat Gold Pave Set Ring
By Sebastian Bernard
Located in Los Angeles, CA
18K Gold Pave Set Diamond Ring with Oval Shaped Center comprised of 20 Invisible Set Princess Cut
Category

2010s American Contemporary Fashion Rings

Materials

Diamond, Blue Sapphire, 18k Gold

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

18 Karat Yellow Gold 6.00 Carat Ruby 1.42 Carat Diamond Earrings
Located in New York, NY
. 42 rubies= 6.00 carats 20 diamonds = 1.42 carats Stamped 18K
Category

Vintage 1980s American Contemporary Clip-on Earrings

Materials

Diamond, Ruby, 18k Gold, Yellow Gold

1.4 Carat Ruby Diamond 18 Karat Cocktail Ring
By Meghna Jewels
Located in Hoffman Estate, IL
This stunning ring has been meticulously crafted from 18-karat rose gold. Handcrafted in 1.4 carats
Category

21st Century and Contemporary Unknown Contemporary Cocktail Rings

Materials

Diamond, Ruby

2.32 Carat Pear Brilliant Diamond 18 Karat Gold Eternity Ring
By Sebastian Bernard
Located in Los Angeles, CA
This beautiful Eternity Ring is made in 18K Gold with 12 perfectly matched Pear Brilliant Diamonds
Category

2010s American Wedding Rings

Materials

Diamond, 18k Gold

5 Carat Rubelite and 4.5 Carat Diamond 18 Karat White Gold Cocktail Ring Estate
Located in New York, NY
A classic, Cocktail ring 5 Carat Rubelite and 4.5 Carat Diamond 18 Karat White Gold Cocktail Ring
Category

2010s Cocktail Rings

Materials

Diamond, Rubelite, 18k Gold, Gold, White Gold

18 karat 2.50 carat two-row princess diamond band VS quality
Located in Laguna Hills, CA
An 18-karat yellow gold band showcasing two rows of meticulously arranged diamonds in a channel-set
Category

21st Century and Contemporary American Contemporary Band Rings

Materials

Diamond, 18k Gold, Yellow Gold

1.16 Carat Diamond and 4.86 Carat Ruby Pendant in 18 Karat Gold
Located in Bangkok, TH
A brand new diamond and ruby pendant in 18 karat gold. Diamond weigh 1.16 carat and ruby weigh 4.86
Category

2010s Pendant Necklaces

Materials

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

Vintage Diamond and 18 Carat Gold Stud Earrings
Located in Chipping Campden, GB
measuring 50pts each. Set in platinum and modelled in 18 Carat gold. Stud Height From Ear: 5.5mm Weight
Category

Vintage 1950s Unknown Modern Stud Earrings

Materials

Diamond, Gold, 18k Gold

18 Carat White Gold Diamond Cascade Waterfall Necklace
Located in London, GB
Crafted in 18 carat white gold, this elegant diamond cascade necklace showcases a delicate
Category

2010s Italian Modern Pendant Necklaces

Materials

Diamond, 18k Gold, White Gold

An 18 carat gold Tronchetto Bulgari ring with diamonds
By Bulgari
Located in Amsterdam, NL
An 18 carat gold ring set with brilliant cut diamonds (app. 0.66 carats G-H, Vs, Signed: Bulgari
Category

Vintage 1980s Italian Band Rings

Materials

Diamond, White Diamond, Gold, 18k Gold

14.5 Carat Cushion Shape Rhodolite Garnet and 2 Carat Diamond Ring 18 Karat Gold
Located in New York, NY
14.5 Carat Cushion Shape Rhodolite Garnet & 2 Ct Diamond Ring 18 Kt White Gold, Estate This
Category

2010s Engagement Rings

Materials

Diamond, Garnet, 18k Gold, White Gold

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

1990s Italian Artisan Band Rings

Materials

Diamond, 18k Gold, White Gold

Vintage Diamond and 18 Carat Gold Solitaire Ring
Located in Chipping Campden, GB
This simply stunning ring holds a clean and bright diamond measuring approximately 70pts. The
Category

Antique Early 1900s British Edwardian Solitaire Rings

Materials

Diamond, 18k Gold, Gold

Natural Diamond 0.83 carats 18 Karats White Gold Flower Stud Earrings
Located in Antwerpen, BE
-cut diamonds. The 0.83 total carats of high-quality diamonds are meticulously arranged to create a
Category

2010s Belgian Modern Stud Earrings

Materials

Diamond, 18k Gold, White Gold

Modern Diamond and 18 Carat White Gold Eternity Ring
Located in Chipping Campden, GB
and the band is modelled in 18 carat white gold. Diamond total of this ring is approx 1.5ct. * please
Category

Early 2000s British Wedding Rings

Materials

Diamond, White Gold

1.05 Carat Natural Round Cut Diamond Hoop Earrings 18 Karat White Gold
By Roshe Jewels
Located in Los Angeles, CA
1.05 Carat Natural Round Cut Diamond Hoop Earrings 18 Karat White Gold These versatile beauties
Category

2010s American Contemporary Hoop Earrings

Materials

Diamond, 18k Gold, White Gold

Vintage Diamond Platinum and 18 Carat Gold Ring
Located in Chipping Campden, GB
On top of this simple 18 Carat Gold band sits seven bright diamonds with a total weight of 70pts
Category

Vintage 1960s British Modern More Rings

Materials

Diamond, Gold, Platinum

2.60 Carat Natural Colombian Emerald Diamond Drop Earrings 18 Karat Gold
By Emeralds Maravellous
Located in US
Stylish 2.60 Carat Natural Colombian Emerald Diamond Dangle Drop Earrings 18K Gold Primary Stones
Category

21st Century and Contemporary American Contemporary Drop Earrings

Materials

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

PANIM 15.29 Carat Diamond Briolette Beads 18 Karat White Gold Necklace
By PANIM
Located in Tsim Sha Tsui, Hong Kong
PANIM 15.29 Carat Diamond Briolette & Beads 18 Karat White Gold 24" Necklace This Panim exquisite
Category

21st Century and Contemporary Indian Modern Link Necklaces

Materials

Diamond, White Diamond, 18k Gold, White Gold

Edwardian Sapphire and Diamond 18 Carat Gold Cluster Ring
Located in Chipping Campden, GB
This striking sapphire and diamond cluster ring is modelled in 18 Carat Gold and the stones are set
Category

Antique Early 1900s Unknown Cluster Rings

Materials

Diamond, Sapphire, Gold, Platinum

PANIM 30 Carat Diamond Briolette 18 Karat White Gold Tassel Earrings
By PANIM
Located in Tsim Sha Tsui, Hong Kong
29.75 Carats of Diamond Briolette Set in Earrings having 18k White Gold
Category

21st Century and Contemporary Indian Modern Lever-Back Earrings

Materials

Diamond, White Diamond, 18k Gold, White Gold

8.46 Carat Amethyst and 0.96 Carat Diamond Ring in 18 Karat Gold
Located in Bangkok, TH
A brand new amethyst and diamond ring in 18 karat gold. The total amethyst weigh 8.46 carat and
Category

2010s Fashion Rings

Materials

Amethyst, Diamond, Gold, 18k Gold, White Gold

10.76 Carats Midcentury Style Emerald and Diamond Drop Earrings 18 Karat
By Emeralds Maravellous
Located in US
style, hand fabricated in gleaming 18K white gold. Total diamond 2.80 carats H-SI1-SI2. Gemstone's total
Category

21st Century and Contemporary American Art Deco Drop Earrings

Materials

Diamond, White Diamond, Emerald, 18k Gold, White Gold

3.17 Carat Tsavorite and 1.51 Carat Diamond Ring in 18 Karat Gold
Located in Bangkok, TH
A brand new tsavorite and diamond ring in 18 karat gold. The tsavorite weigh 3.17 carat and diamond
Category

2010s Fashion Rings

Materials

Diamond, Tsavorite, Gold, 18k Gold, White Gold

PANIM 1.39 Carats Diamond Rosecut 18 Karat White Gold Floral Ring
By PANIM
Located in Tsim Sha Tsui, Hong Kong
PANIM 1.39 Carat Diamond Rosecut 18 Karat White Gold Floral Ring Set in 18K White Gold this ring
Category

21st Century and Contemporary Indian Modern Cocktail Rings

Materials

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

Diamond 18 Carat White Gold Linear Drop Earrings
Located in London, GB
. The sparkling diamonds alternate with five 18 carat white gold round shaped links featuring a perfect
Category

Early 2000s English Modern Drop Earrings

Materials

Diamond, Gold, 18k Gold, White Gold

18 Karat Gold 12.7 Carat Yellow Diamond and Diamond Tennis Bracelet
By Gems Paradise
Located in Jaipur, IN
stunning 12.7 carats of yellow and white diamonds. Each diamond is expertly selected for its exceptional
Category

2010s Indian Modern Tennis Bracelets

Materials

Diamond, Yellow Diamond, 18k Gold

Natural Diamond 0.63 carats 18 KT White Gold Anniversary Band Ring
Located in Antwerpen, BE
its allure, adorned with a double row of sparkling diamonds totaling 0.63 carats. A classic gets a
Category

2010s Belgian Modern Band Rings

Materials

Diamond, 18k Gold, White Gold

Ring Yellow Gold 18 Carats Princess Cut Diamond
Located in Vannes, FR
Ring Yellow Gold 18 Carats Princess Cut Diamond This stunning ring is a masterpiece crafted in
Category

21st Century and Contemporary French Contemporary Cocktail Rings

Materials

Diamond, Gold, 18k Gold, Yellow 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 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 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 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 ExpertFebruary 22, 2021
    Depending on the quality, age, and designer, a 1-carat diamond can cost between $1,300 and $16,500.
  • 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 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.