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18 Carat Diamond

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1.46 Carat Round Brilliant Diamond Ring 18 Karat Yellow Gold
Located in BEVERLY HILLS, CA
. Complimented by 0.37 carats of round brilliant diamonds, approximately H/I color and SI clarity. 18-karat
Category

21st Century and Contemporary American Contemporary Engagement Rings

Materials

Diamond, White Diamond, 18k Gold, Yellow Gold

18 Carat White Gold Three Row Diamond Bracelet
Located in London, GB
any attire. The bracelet features three rows of delicate 18 carat white gold diamond set bar links
Category

21st Century and Contemporary Unknown Modern Modern Bracelets

Materials

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

1960s 7.32 Carat Opal Diamond 18 Carat Rose Gold Retro Ring
Located in Poitiers, FR
golden threads that come together to form the base. Total weight of the opal: 7.32 carat Total diamond
Category

Vintage 1960s French Retro Cocktail Rings

Materials

Diamond, Opal, White Diamond, 18k Gold, Gold, Rose Gold

18 Karat Yellow Gold Round Halo Diamond Earrings 1 Carat
Located in San Francisco, CA
These delicate earrings feature two round shaped diamonds that are approximately 0.70-carat total
Category

21st Century and Contemporary American More Earrings

Materials

Diamond, Yellow Gold

18 Karat White Gold Round Halo Diamond Earrings 1 Carat
Located in San Francisco, CA
These delicate earrings feature two round shaped diamonds that are approximately 0.70-carat total
Category

21st Century and Contemporary American More Earrings

Materials

Diamond, White Gold

18 Karat Yellow Gold Oval Halo Diamond 1/3 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.23-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Yellow Gold

18 Karat Yellow Gold Halo Diamond Pendant 1/2 Carat
Located in San Francisco, CA
This delicate pendant feature one round shaped diamond that is approximately 0.35-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Halo Diamond Pendant 3/4 Carat
Located in San Francisco, CA
This delicate pendant features one round shaped diamonds that are approximately 0.54-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Halo Diamond Pendant 3/4 Carat
Located in San Francisco, CA
This delicate pendant features one round shaped diamonds that are approximately 0.54-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, White Gold

18 Karat Yellow Gold Halo Diamond Pendant 3/4 Carat
Located in San Francisco, CA
This delicate pendant features one round shaped diamonds that are approximately 0.54-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Halo Diamond Pendant 1/2 Carat
Located in San Francisco, CA
This delicate pendant feature one round shaped diamond that is approximately 0.35-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Halo Diamond Pendant 1/2 Carat
Located in San Francisco, CA
This delicate pendant feature one round shaped diamond that is approximately 0.35-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, White Gold

18 Karat Yellow Gold Oval Halo Diamond 1/2 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.47-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Oval Halo Diamond 1/2 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.47-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Oval Halo Diamond 1/3 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.23-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, White Gold

18 Karat Rose Gold Oval Halo Diamond 3/4 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.70-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Rose Gold

18 Karat Rose Gold Oval Halo Diamond 1/3 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.23-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Rose Gold

18 Karat White Gold Oval Halo Diamond 3/4 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.70-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, White Gold

18 Karat White Gold Oval Halo Diamond 1/2 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.47-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, White Gold

18 Karat Yellow Gold Oval Halo Diamond 3/4 Carat
Located in San Francisco, CA
This delicate pendant features one oval-shaped diamond that is approximately 0.70-carat total
Category

21st Century and Contemporary American Pendant Necklaces

Materials

Diamond, Yellow Gold

2.32 Carat Fancy Color Diamond 18 Karat White Gold Cocktail Ring
By Roshe Jewels
Located in Los Angeles, CA
2.26 Carat Fancy Color Diamond 18 Karat White Gold Cocktail Ring This magnificent beauty has Fancy
Category

21st Century and Contemporary American Contemporary Cocktail Rings

Materials

Diamond, White Diamond, Yellow Diamond, Brown Diamond, Gold, 18k Gold, W...

18 Carat White Gold Emerald And Diamond Ring
Located in Vannes, FR
sugar pine, capturing the light with exceptional brilliance. Framed by two diamonds of 0.440 carats each
Category

21st Century and Contemporary French Modern Fashion Rings

Materials

Diamond, Emerald, 18k Gold, White Gold

18 Karat Gold 0.25 Carat Diamond Drop Earrings
By Gems Paradise
Located in Jaipur, IN
Delicately crafted in 18 Karat Gold, these drop earrings feature 0.25 carats of finely cut diamonds
Category

2010s Indian Modern Drop Earrings

Materials

Diamond, Gold, 18k Gold

Art Deco Diamond 18 Carat Gold Crescent Brooch
Located in Chipping Campden, GB
This gorgeous crescent is modelled in 9 carat gold. The larger diamonds are old mine cut and the
Category

Vintage 1910s European Art Deco Brooches

Materials

Diamond, Gold

1.4 Carat Natural Oval Ruby and 0.80 Carat Diamond 18 Karat Gold Ring
Located in New York, NY
Introducing our exquisite 18 Karat Gold Ring, featuring a stunning 1.4 carat natural oval Ruby and
Category

Early 2000s Solitaire Rings

Materials

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

18 Carats VS E Quality Diamond 18 Karat White Gold Necklace Bridal Brand New
Located in New York, NY
18.5 Carats VS, E Diamond Necklace made in 18 Karat white gold . One of our premium necklace
Category

2010s Drop Necklaces

Materials

Diamond, 18k Gold, White Gold

18 Karat Gold Natural Jade and Diamond Buddha Pendant 75.94 Carat
Located in Washington Depot, CT
18K White Gold Natural Jade and Diamond Large Buddha Pendant This happy Buddha pendant is set in
Category

Late 20th Century More Jewelry

Materials

Diamond, Jade, 18k Gold

2.63 Carat Tourmaline Diamond 18 Karat White Gold Bridal Ring
By Roshe Jewels
Located in Los Angeles, CA
Cushion cut 1.87 Carat Tourmaline and is surrounded by 22 Round Cut Diamonds that weigh 0.76 Carats. The
Category

21st Century and Contemporary American Modern Cocktail Rings

Materials

Diamond, Tourmaline, 18k Gold, White Gold

1.96 Carat Ruby Diamond 18 Karat White Gold Cocktail Ring
By DGI
Located in Los Angeles, CA
A simple yet beautiful ring with a 0.59 Carat Pear Cut Ruby as its center and 56 Round Cut Diamonds
Category

2010s American Contemporary Cocktail Rings

Materials

Diamond, Ruby, 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 35pts. The
Category

Early 2000s British Solitaire Rings

Materials

Diamond, Gold, 18k Gold

Quartz Diamonds 18 Carat White Gold Drop Earrings
By SCALA GIOIELLI
Located in Marcianise, IT
are elegantly accented with brilliant-cut diamonds (0.47 carats ) set in two key areas: The Cap: A V
Category

Early 2000s Italian Artisan Drop Earrings

Materials

Diamond, Quartz, 18k Gold, White Gold

2.40 Carat Natural Peridot Diamond 18 Karat White Gold Engagement Ring
By Roshe Jewels
Located in Los Angeles, CA
2.40 Carat Natural Peridot Diamond 18 Karat White Gold Engagement Ring This beautiful ring has a
Category

21st Century and Contemporary American Contemporary Engagement Rings

Materials

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

2.5 Carat 5 Stone Emerald Cut Diamond 18 Carats Yellow Gold Band Ring
By Antinori Fine Jewels
Located in Chicago, IL
2.5 ct total weight Five 5-Stone Asscher Cut Diamond Wedding Band / Ring in 18K Yellow Gold. The
Category

2010s American Contemporary Solitaire Rings

Materials

Diamond, Emerald, 18k Gold, Yellow Gold

Alexander 25.17 Carat Diamond Tennis Necklace 18 Karat White Gold
By Alexander Beverly Hills
Located in BEVERLY HILLS, CA
diamonds, 25.17 carats. Approximately G/H color and SI clarity. 18k white gold, 31.28 grams, 16in
Category

21st Century and Contemporary American Contemporary More Necklaces

Materials

Diamond, White Diamond, 18k Gold, White Gold

18 Karat Rose Gold Bolo Diamond Bracelet 1/2 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 0.49 Metal: 18K Rose Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Rose Gold

18 Karat White Gold Bolo Diamond Bracelet 1/2 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 0.49 Metal: 18K White Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, White Gold

1.16 Carat Yellow Sapphire Diamond 18 Karat Rose Gold Ring
By Roshe Jewels
Located in Los Angeles, CA
Round Cut Diamonds that weigh 0.54 Carats. The Total Carat Weight of the ring is 1.16 Carats. The ring
Category

21st Century and Contemporary American Contemporary Engagement Rings

Materials

Diamond, Yellow Sapphire, 14k Gold, Rose Gold

18 Karat White Gold Channel Princess Diamond Bangle 2.5 Carat
Located in San Francisco, CA
Gemstone Color: WHITE Center Gemstone Shape: PRINNCESS Center Diamond Carat Weight: 2.5 Metal: 18K White
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, White Gold

18 Karat Rose Gold Petite Halo Diamond Bangle 1 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 0.95 Metal: 18K Rose Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Petite Halo Diamond Bangle 1 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 0.95 Metal: 18K Yellow Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Yellow Gold

18 Karat White Gold Petite Halo Diamond Bangle 1 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 0.95 Metal: 18K White Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, White Gold

18 Karat Yellow Gold Micro-Prong Diamond Bangle 2 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 2.08 Metal: 18K Yellow Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Yellow Gold

18 Karat Rose Gold Micro-Prong Diamond Bangle 1 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 1 Metal: 18K Rose Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Rose Gold

18 Karat Yellow Gold Micro-Prong Diamond Bangle 1 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 1 Metal: 18K Yellow Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Yellow Gold

18 Karat White Gold Micro-Prong Diamond Bangle 1 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 1 Metal: 18K White Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, White Gold

18 Karat White Gold Micro-Prong Diamond Bangle 2 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 2.08 Metal: 18K White Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, White Gold

18 Karat Rose Gold Micro-Prong Diamond Bangle 2 Carat
Located in San Francisco, CA
: WHITE Center Gemstone Shape: ROUND Center Diamond Carat Weight: 2.08 Metal: 18K Rose Gold Metal Weight
Category

21st Century and Contemporary American More Bracelets

Materials

Diamond, Rose Gold

2.50 Carat Natural Diamond Drop Bezel Necklace 14K White Gold 18
Located in New York, NY
2.50 Carat Natural Diamond Drop Necklace 14K White Gold G SI 18 inches chain 100% Natural Diamonds
Category

2010s American Romantic Drop Necklaces

Materials

Diamond, White Gold, 14k Gold

7.5 Carat Oval Rubellite and 1 Carat Diamond 18 Karat Gold Cocktail Ring Estate
Located in New York, NY
7.5 Carat Oval Rubellite & 1 Carat Diamond 18 Karat Gold Cocktail Ring Estate A classic, Cocktail
Category

2010s Cocktail Rings

Materials

Diamond, Tourmaline, 18k Gold

Vintage Amethyst and Diamond 18 Carat Gold Ring
Located in Chipping Campden, GB
either side of the central stone. Diamond total 10pts. Modelled in 18 carat gold. Amethyst dimensions
Category

Vintage 1980s British Three-Stone Rings

Materials

Amethyst, Diamond, Gold

Certified 4.51 Carat Brilliant Cut Diamond 18-Karat Gold Earring Studs
Located in Monte Carlo, MC
and 2.25 carat, both I VVS2, set on 18 Karat white gold stud earrings. The diamonds look incredibly
Category

2010s French Contemporary Stud Earrings

Materials

Diamond, White Diamond, 18k Gold, White Gold

18" Natural White Diamond(3.80 carat) Necklace in 18 Karat White Gold
Located in New York, NY
. Perfect for layering or wearing solo. Made in NYC Length: 18" Beads: 38pcs 3.2-3.5mm white diamond
Category

Early 2000s American Link Necklaces

Materials

White Diamond, 18k Gold, White Gold

6.16 Carat Sapphire Diamond 18 Karat White Gold Bridal Ring
By Roshe Jewels
Located in Los Angeles, CA
6.16 Carat Sapphire Diamond 18 Karat White Gold Bridal Ring Beautiful and Charming Cabochon Cut
Category

21st Century and Contemporary American Modern Cocktail Rings

Materials

Diamond, Blue Sapphire, Sapphire, White Gold, 18k Gold

4.28 Carat Ruby Diamond Ring in 18 Karat White Gold
Located in Great Neck, NY
carats Two Triangle Diamonds weighing .42 carats Diamonds are GH-SI1 Set in 18 karat white gold ring 6.21
Category

2010s American Modern Cocktail Rings

Materials

Diamond, Ruby, 18k Gold, White Gold

Ruby and Diamond 18 Carat Yellow Gold Bracelet
Located in London, GB
weight of 8.00 carats, all mounted in 18 carat yellow gold. The vibrant rubies are set in multiple
Category

Early 2000s Unknown Retro Bracelets

Materials

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

18 karat white gold, 3.50 carat diamond princess, invisible halo ring
Located in Laguna Hills, CA
baguette cut diamonds, totaling 3.50 carats. The sturdy mounting, with a honeycomb double gallery, ensures
Category

21st Century and Contemporary American Contemporary Cocktail Rings

Materials

Diamond, White Gold

Blue White Diamond Necklace 1.50 Carat Invisible Style 18 Karat
Located in Laguna Hills, CA
18 karat white gold pendant with princess cut blue and white diamonds. The excellently styled
Category

21st Century and Contemporary American Contemporary Pendant Necklaces

Materials

White Diamond, Blue Diamond, 18k Gold, White 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 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 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 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 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 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 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 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 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 ExpertNovember 1, 2023
    Whether two-carat diamond studs are too big is a matter of personal preference. At this size, each earring will be one carat. If you opt for the classic round brilliant cut, the studs will typically measure around 6.5 millimeters in diameter, which is a little more than half the size of a dime. Find a wide range of diamond stud earrings on 1stDibs.
  • 1stDibs ExpertNovember 8, 2023
    Whether 1.3-carat diamond earrings are too small is a matter of personal opinion. A pair of earrings with a total carat weight of 1.3 is considered to be medium-sized. The smallest diamond earrings are around 0.25 carats, while the largest are 1.5 carats or more. Explore a wide range of diamond earrings on 1stDibs.
  • 1stDibs ExpertNovember 27, 2023
    Whether half-carat diamond studs are too small is a matter of personal opinion. A pair of diamond studs with a total carat weight of 0.5 usually consists of two 0.25-carat earrings. Many jewelry makers offer studs as small as 0.13 carats, so many people consider half-carat diamond studs to be medium-sized. On 1stDibs, shop a collection of antique and vintage diamond stud earrings.