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Vintage 14K Gold, Diamond and Multi Gemstone Thai Princess Harem Ring
Located in Derby, NY
Discover the allure of royal heritage with this exquisite Thai Princess Harem Ring, a vintage
Category

Mid-20th Century Dome Rings

Materials

Sapphire, Yellow Sapphire, Ruby, Quartz, Multi-gemstone, Moonstone, Garn...

Ruby Earrings Set in 18 Karat White Gold Settings
Located in Bangkok, TH
Ruby 3.02 carats Earrings set in 18 Karat White Gold Settings Width: 0.6 cm Length: 1.7 cm Total
Category

2010s Thai Contemporary Lever-Back Earrings

Materials

Ruby, White Gold

9K Gold Natural Ruby Cluster Vintage Style Drop Earrings
Located in Bangkok, TH
A stunning natural ruby cluster at the center, encased in intricate open work detailing. The
Category

21st Century and Contemporary Thai Edwardian Drop Earrings

Materials

Ruby, 9k Gold, Yellow Gold

Ruby Earrings set in 18K White Gold Settings
Located in Bangkok, TH
Ruby 14.94 carats Earrings set in 18K White Gold Settings Width: 1.6 cm Length: 5.0 cm Total
Category

2010s Thai Contemporary Chandelier Earrings

Materials

Ruby, 18k Gold, White Gold

White Gold Ruby Diamond Flower Stud Earrings
By La Fleur Jewels
Located in Bangkok, TH
The top quality ruby which make in invisible setting. We set the stone in perfection as we are
Category

21st Century and Contemporary Thai Modern Clip-on Earrings

Materials

Diamond, Ruby, 18k Gold, White Gold

18K Gold 0.90ct Squared Ruby 0.04ct Diamond Hoop Earrings
Located in เกาะสมุย, TH
arrangement of squared rubies totaling approximately 0.90 carats. Each of two vivid red stones are framed by
Category

21st Century and Contemporary Thai Hoop Earrings

Materials

Diamond, Ruby, 18k Gold

Small Invisibly-Set Ruby Diamond Clover Earrings
Located in Palm Beach, FL
Four-leaf clover stud earrings, designed as an invisibly-set calibre-cut ruby clover centering a
Category

2010s Thai Stud Earrings

Materials

Diamond, Ruby, 18k Gold, White Gold

Geoart Ruby, Diamond Stud Earrings 18k Yellow Gold
By Kavant Sharart
Located in Bangkok, 10
Ruby 0.72 carat with Diamond 0.24 carat Earrings set in 18K Gold Settings Width: 1.2 cm Length
Category

2010s Thai Stud Earrings

Materials

Diamond, Ruby, 18k Gold, Yellow Gold

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 15.61 carats with Diamond 0.70 carat Earrings set in 18K Gold Settings Width: 1.4 cm Length
Category

2010s Thai Contemporary Stud Earrings

Materials

Diamond, Ruby, 18k Gold

Emerald Cut Ruby Classic Halo Ring 2.39 Carats
Located in Bangkok, TH
This refined ring features a 2.39 carat emerald cut natural ruby, admired for its rich red color
Category

2010s Thai Contemporary Cocktail Rings

Materials

Ruby, Diamond, Yellow Gold, 18k Gold

MOISEIKIN 1.64ct No Heat Ruby Necklace
By MOISEIKIN
Located in Hong Kong, HK
creativity. This Ruby necklace with a 1.64ct No Heat Mozambique Ruby is inspired by the Music of Colours
Category

2010s Thai Contemporary Pendant Necklaces

Materials

Diamond, Sapphire, Emerald, Ruby, 18k Gold, White Gold

ARAYIAN Cluster Burma Ruby and Diamond Earrings
Located in Khet Bang Rak, 10
Gold: 5.44 grams Rubies: 6 pieces, 3.70 carats Diamonds: 12 pieces, 1.62 carats A pair of
Category

21st Century and Contemporary Thai Modern Stud Earrings

Materials

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

Ruby Pendant set in 18 Karat Gold Settings
Located in Bangkok, TH
Ruby 1.30 carats Pendant set in 18 Karat Gold Settings (chain not included) Width: 0.4 cm Length
Category

2010s Thai Contemporary Pendant Necklaces

Materials

Ruby, Gold, 18k Gold

Cabochon Ruby Ring set in 18K Gold Settings
Located in Bangkok, TH
Cabochon Ruby 1.61 carats Ring set in 18K Gold Settings Width: 1.0 cm Length: 1.0 cm Ring Size
Category

2010s Thai Contemporary Solitaire Rings

Materials

Ruby, 18k Gold

Ruby Earrings set in 18K White Gold Settings
Located in Bangkok, TH
Ruby 4.33 carats Earrings set in 18K White Gold Settings Width: 0.4 cm Length: 2.3 cm Total
Category

2010s Thai Contemporary Lever-Back Earrings

Materials

Ruby, 18k Gold, White Gold

Ruby Earrings set in 18K Rose Gold Settings
Located in Bangkok, TH
Ruby 9.31 carats Earrings set in 18K Rose Gold Settings Width: 1.6 cm Length: 2.3 cm Total
Category

2010s Thai Contemporary Clip-on Earrings

Materials

Ruby, 18k Gold, Rose Gold

Ruby Bangle Set in 18k Rose Gold Settings
Located in Bangkok, TH
Ruby 11.85 carats Bangle set in 18K Rose Gold Settings Width: 2.8 cm Diameter: 6.2 cm Total
Category

2010s Thai Contemporary Bangles

Materials

Ruby, 18k Gold, Rose Gold

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 1.93 carats with Diamond 0.29 carat Earrings set in 18K Gold Settings Width: 0.9 cm Length
Category

2010s Thai Contemporary Stud Earrings

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 1.98 carats with Diamond 0.12 carat Earrings set in 18K Gold Settings Width: 0.6 cm Length
Category

2010s Thai Contemporary Lever-Back Earrings

Materials

Diamond, Ruby, 18k Gold

ARAYIAN 2.59 Unheated Mozambique Ruby Earrings with Certificate
Located in Khet Bang Rak, 10
A perfectly matching unheated Mozambique ruby earrings. Rubies are known as the king of gems, and
Category

21st Century and Contemporary Thai Modern Stud Earrings

Materials

Diamond, Ruby, 18k Gold, White Gold

Star Ruby Ring set in 18K White Gold Settings
Located in Bangkok, TH
Star Ruby 2.78 carats Ring set in 18K White Gold Settings Width: 1.3 cm Length: 0.8 cm Ring Size
Category

2010s Thai Contemporary Solitaire Rings

Materials

Ruby, Star Ruby, 18k Gold, White Gold

Cabochon Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Cabochon Ruby 6.17 carats with Diamond 1.14 carat Earrings set in 18K Gold Settings Width: 1.3 cm
Category

2010s Thai Contemporary Stud Earrings

Materials

Diamond, Ruby, 18k Gold

Ruby Earrings Set in 18 Karat White Gold Settings
Located in Bangkok, TH
Ruby 2.60 carats Earrings set in 18 Karat White Gold Settings Width: 0.6 cm Length: 2.1 cm Total
Category

2010s Thai Clip-on Earrings

Materials

Ruby, 18k Gold, White Gold

Ruby Cross Pendant Set in 18 Karat Gold Settings
Located in Bangkok, TH
Ruby 13.50 carats Cross pendant set in 18 Karat Gold Settings (chain not included) Width: 5.1 cm
Category

2010s Thai Pendant Necklaces

Materials

Ruby, Gold, 18k Gold

Cushion Cut Ruby Ring set in 18K Gold Settings
Located in Bangkok, TH
Ruby 6.56 carats Ring set in 18K Gold Settings Width: 1.1 cm Length: 1.1 cm Ring Size: 52 Total
Category

2010s Thai Contemporary Solitaire Rings

Materials

Ruby, 18k Gold

Ruby with Diamond Necklace set in 18K Gold Settings
Located in Bangkok, TH
Ruby 46.20 carats with Diamond 4.55 carats Necklace set in 18K Gold Settings Width: 1.2 cm Length
Category

2010s Thai Contemporary Link Necklaces

Materials

Diamond, Ruby, 18k Gold

Ruby and Diamond Ring set in Platinum 950 Settings
Located in Bangkok, TH
Ruby 0.68 carat and Diamond 0.50 carat Ring set in Platinum 950 Settings Width: 1.2 cm Length
Category

2010s Thai Contemporary Three-Stone Rings

Materials

Diamond, Ruby, Platinum

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 10.16 carats with Diamond 1.42 carats Earrings set in 18K Gold Settings Width: 2.2 cm Length
Category

2010s Thai Contemporary Clip-on Earrings

Materials

Diamond, Ruby, 18k Gold

Emerald with Ruby Ring Set in Platinum 950 Settings
Located in Bangkok, TH
Emerald 2.85 carats with Ruby 2.09 carats Ring set in Platinum 950 settings Width: 2.0 cm Length
Category

2010s Thai Three-Stone Rings

Materials

Emerald, Ruby, Platinum

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 3.43 carats with Diamond 0.65 carat Earrings set in 18K Gold Settings Width: 1.0 cm Length
Category

2010s Thai Contemporary Stud Earrings

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 2.63 carats with Diamond 0.46 carat Earrings set in 18K Gold Settings Width: 0.9 cm Length
Category

2010s Thai Contemporary Stud Earrings

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Bangle set in 18K Gold Settings
Located in Bangkok, TH
Ruby 16.42 carats with Diamond 3.58 carats Bangle set in 18K Gold Settings Width: 2.0 cm
Category

2010s Thai Contemporary Bangles

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Bangle set in 18K Gold Settings
Located in Bangkok, TH
Ruby 26.35 carats with Diamond 1.21 carats Bangle set in 18K Gold Settings Width: 1.9 cm
Category

2010s Thai Contemporary Bangles

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Bangle set in 18K Gold Settings
Located in Bangkok, TH
Ruby 19.41 carats with Diamond 3.01 carats Bangle set in 18K Gold Settings Width: 2.0 cm
Category

2010s Thai Contemporary Bangles

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Earrings set in Platinum 950 Settings
Located in Bangkok, TH
Ruby 3.20 carats with Diamond 0.90 carat Earrings set in Platinum 950 Settings Width: 1.5 cm
Category

2010s Thai Art Deco Drop Earrings

Materials

Diamond, Ruby, Platinum

Ruby with Diamond Pendant set in 18K Gold Settings
Located in Bangkok, TH
Ruby 6.86 carats with Diamond 1.61 carats Pendant set in 18K Gold Settings (chain not included
Category

2010s Thai Contemporary Pendant Necklaces

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Earrings set in 18K Gold Settings
Located in Bangkok, TH
Ruby 3.10 carats with Diamond 0.16 carat Earrings set in 18K Gold Settings Width: 0.6 cm Length
Category

2010s Thai Contemporary Stud Earrings

Materials

Diamond, Ruby, 18k Gold

Ruby Cufflinks Set in 18 Karat White Gold Settings
Located in Bangkok, TH
Ruby 2.89 carats Cufflinks set in 18 Karat White Gold Settings Width: 1.7 cm Length: 1.0 cm
Category

2010s Thai Cufflinks

Materials

Ruby, 18k Gold, White Gold

0.970 Carat Ruby with Diamond Ring in 18 Karat Gold
Located in Bangkok, 10
timeless design. At its center, a stunning 0.970-carat oval-cut ruby commands attention with its deep red
Category

2010s Thai Solitaire Rings

Materials

Diamond, Ruby, Gold

Ruby Leaf Brooch 18 Carat White Gold
By La Fleur Jewels
Located in Bangkok, TH
looks not too much but it looks classic and precious. We use the top quality ruby which make in
Category

21st Century and Contemporary Thai Modern Brooches

Materials

Diamond, Ruby, 18k Gold, White Gold

ARAYIAN 1.33-Carat Ruby with Diamond Halo Ring
Located in Khet Bang Rak, 10
Ruby – 1.33 carats Diamond – 0.76 carats Gold – 4.63 grams A perfect 1.33-carat ruby engagement
Category

21st Century and Contemporary Thai Modern Engagement Rings

Materials

Diamond, Ruby, 18k Gold, White Gold

18 White Gold Flower Ruby Invisible Stud Earrings
By La Fleur Jewels
Located in Bangkok, TH
A lovely ruby stud earrings that you can use as everyday. We use the top quality Ruby for our
Category

21st Century and Contemporary Thai Modern Stud Earrings

Materials

Diamond, Ruby, 18k Gold, White Gold

Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Ruby 1.23 carats with Diamond 0.51 carat Ring set in 18K Gold Settings Width: 1.0 cm Length: 1.1
Category

2010s Thai Contemporary Engagement Rings

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Ruby 2.73 carats with Diamond 0.98 carat Ring set in 18K Gold Settings Width: 1.3 cm Length: 1.5
Category

2010s Thai Contemporary Solitaire Rings

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Ruby 9.14 carats with Diamond 0.48 carat Ring set in 18K Gold Settings Width: 1.8 cm Length: 2.3
Category

2010s Thai Contemporary Three-Stone Rings

Materials

Diamond, Ruby, 18k Gold

Baguette Ruby Tassle Earrings with Diamond Knot
Located in Hong Kong, HK
The Baguette Ruby Tassle Earrings with Diamond Knot are truly a work of art. Crafted from luxurious
Category

Early 2000s Thai Contemporary Dangle Earrings

Materials

Diamond, Ruby, 18k Gold, White Gold

Talay Flow Wave Ruby Ring in 18K Rose Gold
By Kavant Sharart
Located in Bangkok, 10
Talay Flow Wave Ruby 2.10 carats Ring in 18K Rose Gold Width: 2.0 cm Length: 0.5 cm The Skinny
Category

2010s Thai Band Rings

Materials

Ruby, 18k Gold, Rose Gold

Star Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Star Ruby 10.05 carats with Diamond 0.77 carat Ring set in 18K Gold Settings Width: 2.0 cm
Category

2010s Thai Contemporary Solitaire Rings

Materials

Diamond, Ruby, Star Ruby, 18k Gold

Star Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Star Ruby 7.95 carats with Diamond 0.34 carat Ring set in 18K Gold Settings Width: 1.6 cm Length
Category

2010s Thai Contemporary Solitaire Rings

Materials

Diamond, Ruby, Star Ruby, 18k Gold

Ruby Heart Earrings set in 18K White Gold Settings
Located in Bangkok, TH
Ruby 0.47 carat Earrings set in 18K White Gold Settings Width: 1.0 cm Length: 1.0 cm Total Weight
Category

2010s Thai Contemporary Stud Earrings

Materials

Ruby, 18k Gold, White Gold

Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Ruby 4.82 carats with Diamond 0.52 carat Ring set in 18K Gold Settings Width: 1.3 cm Length: 1.8
Category

2010s Thai Contemporary Solitaire Rings

Materials

Diamond, Ruby, 18k Gold

Ruby with Diamond Ring set in 18K Gold Settings
Located in Bangkok, TH
Ruby 1.24 carats with Diamond 0.32 carat Ring set in 18K Gold Settings Width: 0.8 cm Length: 0.9
Category

2010s Thai Contemporary Solitaire Rings

Materials

Diamond, Ruby, 18k Gold

18K Gold 0.58ct Oval Ruby 0.12ct Diamond Horseshoe Pendant Enhancer
Located in เกาะสมุย, TH
Race sparklingly towards the finish line with the fiery passion of the ruby! Product Details
Category

20th Century Thai Necklace Enhancers

Materials

Diamond, Ruby, 18k Gold

Ruby Ring Set in 18 Karat Gold Settings
Located in Bangkok, TH
Ruby 9.55 carats Ring set in 18 Karat Gold Settings Width: 2.2 cm Length: 1.0 cm Ring Size: 59
Category

2010s Thai Contemporary More Rings

Materials

Ruby, Gold, 18k Gold

Ruby Ring Set in 18k Rose Gold Settings
Located in Bangkok, TH
Ruby 6.08 carats Ring set in 18K Rose Gold Settings Width: 1.9 cm Length: 2.7 cm Ring Size: 54
Category

2010s Thai Contemporary Cocktail Rings

Materials

Ruby, 18k Gold, Rose Gold

Diamond 0.56 and Ruby Ring set in Platinum 950 Settings
Located in Bangkok, TH
Diamond 0.56 carat and Ruby 0.80 carat Ring set in Platinum 950 Settings Width: 1.2 cm Length
Category

2010s Thai Contemporary Three-Stone Rings

Materials

Diamond, Ruby, Platinum

Ruby Earrings set in 18K Rose Gold Settings
Located in Bangkok, TH
Ruby 7.13 carats Earrings set in 18K Rose Gold Settings Width: 1.6 cm Length: 1.6 cm Total Weight
Category

2010s Thai Contemporary Stud Earrings

Materials

Ruby, 18k Gold, Rose Gold

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Siam Ruby For Sale on 1stDibs

Find the exact siam ruby you’re shopping for in the variety available on 1stDibs. Each design created in this style — which was crafted with great care and often made from Gold, 18k Gold and Platinum — can elevate any look. You can easily find a 28 antique edition and 23 modern creations to choose from as well. Finding the perfect siam ruby may mean sifting through those created during different time periods — you can find an early version that dates to the 19th Century and a newer variation that were made as recently as the 21st Century. For this particular piece, 1 Carat and 1.5 Carat are consistently popular carat weights. Creating a siam ruby has been a part of the legacy of many jewelers, but those produced by Andreoli, Avanti and Berca Atelier are consistently popular. See these pages for an oval cut iteration of this accessory, while there are also cushion cut cut and round cut cut versions available here, too. Finding a siam ruby for sale for women should be easy, but there are 18 pieces available to browse for unisex as well as men, too.

How Much is a Siam Ruby?

Prices for a siam ruby can differ depending upon size, time period and other attributes — at 1stDibs, these accessories begin at $575 and can go as high as $300,116, while this accessory, on average, fetches $12,201.

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 Ruby in Jewelry Design

This deep red gem is the color of heat and passion — vintage and antique ruby jewelry is perfect for those born in the middle of summer.

Rubies are one of the few gemstones that can give diamonds a run for their money. Just consider the Van Cleef Arpels “scarf” necklace the Duke of Windsor presented to the Duchess on her 40th birthday, in 1936 — set with diamonds and dripping with rubies, a testament to the deep-red gemstone’s power — or the slippers encrusted with 4,600 rubies that Harry Winston made to commemorate The Wizard of Oz’s golden anniversary. July babies have permission to adorn themselves with this beautiful red stone even when it’s not their birthday.

Rubies are considered precious stones — along with diamonds, sapphires and emeralds — and have a hardness of 9.0 on the Mohs Scale, surpassed only by Moissanite and diamonds. They are composed of corundum, a colorless mineral that is also the basic material of sapphires. In the July birthstone, the red of the gemstone — and the various hues seen in sapphires — are produced by the presence of trace elements. In the case of a ruby, this element is chromium. Rubies range in color from vermilion to a violet red. They are also pleochroic, which means that a stone’s hue can vary depending on the direction of viewing. The most sought-after color is pigeon’s blood: pure red with a hint of blue.

Rubies that are hosted in dolomite marble are the most prized: Because the marble is low in iron, so are the rubies, resulting in a more intense color. Rubies found in basalt, which has a higher iron content, are generally darker and less intense.

When shopping for antique and vintage ruby jewelry, remember that the 4Cs of selecting the perfect diamond — color, clarity, cut and carat — also apply to rubies.

According to the Gemological Institute of America, the color of the July birthstone should be a vibrant to slightly purplish red, and the stone should be clear and inclusion-free. Accordingly, the cut should show off its color and clarity. As for the last criterion, fine rubies more than a carat in weight are rare. Often, large rubies are more expensive than diamonds of comparable weights.

Find a collection of ruby necklaces, ruby rings and other accessories on 1stDibs.