No Heat 2.80 Carat Sapphire Certified and 1 Carat Diamond PT 900 Stunning Ring
By Malpani Jewels
Located in Hung Hom, HK
A Certified No Heat 2.80 carat blue sapphire is set along side 1.01 carat of white brilliant round diamond in this Platinum PT 900 engagement ring. Sapphires that have not undergone ...
Diamond, Sapphire, Platinum
CGL Certified 0.40 Carat Russian Demantoid Garnet Round Rare Diamond PT 900 Ring
By Malpani Jewels
Located in Hung Hom, HK
One of the rarest garnet varieties, Demantoid can have a green color that rivals emerald and a fire that exceeds diamond. Demantoids are highly prized by both gem collectors and jewe...
Diamond, White Diamond, Garnet, Platinum
$176,000Sale Price|20% Off
GIA Certified 6 Carat Thai Ruby Mirror Clean Rare Investment Ring PT 900
By Malpani Jewels
Located in Hung Hom, HK
First referenced in 1408, Thai Ruby once fulfilled 95 percent of the world's demand for this extremely rare and highly coveted gemstone. Ostensibly depleted since 2009, Thai Ruby is ...
Diamond, White Diamond, Ruby, Platinum
Yellow Gold Emerald & Diamond Vintage Link Bracelet 6 1/2" 18k 900 Rnd 10.08ctw
Located in Greensboro, NC
Era: Vintage Metal Content: 18k Yellow Gold & 900 Platinum Stone Information Natural Emeralds Treatment: Oiling Carat(s): 5.76ctw Cut: Round Color: Green Natural Diamonds Carat(s...
Diamond, Emerald, 18k Gold, Yellow Gold, Platinum
Platinum Wedding Band
Located in Hicksville, NY
Item Details: Ring Size: 3.75 Metal Type: 900 PLATINUM [Hallmarked & Tested] Weight: 1.5 grams Finger to Top of Stone Measurement: 1.2MM Condition: Very Good
Platinum
Platinum Diamond Engagement Ring
Located in New York, NY
The weights are stamped on the inside of the shank along with Pt 900 for platinum. Ring size is 5 and can be sized.
Diamond, Platinum
$960Sale Price|20% Off
Ruby & Diamond Platinum Ring
Located in Bloomington, MN
Ruby & Diamond Platinum Ring This ring is crafted in 900 platinum and features a prong-set red ruby at the center, framed by a balanced mix of round and baguette diamonds.
Diamond, Ruby, Platinum
Platinum Open Wedding Band Ring
Located in Houston, TX
Gender: Ladies Metal Type: 900 Platinum Size: 10.5 Shank Maximum Width: 5.91 mm Weight: 9.80 grams 900 platinum comfort-fit band with a comfort-fit shank.
Platinum
$10,800
Diamond Necklace in Platinum
Located in LA, CA
(Pear Brilliant - 4 pieces/Round Brilliant - 80 pieces) Natural Diamond Shape: Pear Brilliant and Round Brilliant Cut Weight: 2.77 carat total Metal Metal: Platinum Purity: 900
Diamond, Platinum
$71,820Sale Price|20% Off
Graduated Diamond Tennis Necklace in Platinum
Located in Bloomington, MN
Graduated Diamond Tennis Necklace in Platinum This necklace is crafted in 900 platinum and features a continuous line of prong-set round diamonds in a graduated tennis design.
Diamond, Platinum
MK .44 Carat Diamond Yellow Gold Platinum Filigree Platinum Engagement Ring
Located in Stamford, CT
Natural fancy brownish yellow old European cut diamond, approx. total weight .44cts, SI1, Depth: 49.2% Table: 50% GIA certified #5141936351 26 full cut bead set diamonds, approx. to...
Diamond, Yellow Gold, Platinum
$744Sale Price|20% Off
Delicate Tourmaline & Diamond Ring in Platinum
Located in Bloomington, MN
Delicate Tourmaline & Diamond Ring in Platinum This ring is crafted in 900 platinum and features a prong-set pink tourmaline at the center in a classic 3-stone design.
Diamond, Tourmaline, Platinum
Platinum Baguette Cut Diamond Leaf Earrings
Located in New York, NY
Length: 1.15 inches Width: 0.80 inches Markings: "PT.900" Metal: Platinum Weight: 22.9 grams Diamonds: 5.28 carats
Diamond, Platinum
$1,704Sale Price|20% Off
Diamond Geometric Halo Ring in Platinum
Located in Bloomington, MN
Diamond Geometric Halo Ring in Platinum This contemporary ring is crafted in 900 platinum and features a geometric arrangement of baguette and round diamonds.
Diamond, Platinum
$4,788Sale Price|20% Off
Princess Diamond Bridal Set in Platinum
Located in Bloomington, MN
Princess Diamond Bridal Set in Platinum This bridal set is crafted in 900 platinum and features a 1.00 carat princess cut center diamond set in a classic four-prong engagement ring.
Diamond, Platinum
Vintage Platinum 1.45tcw Diamond Five Stone Ring
Located in New York, NY
Weight: 7.5 Grams Stone: 1.45ctw H SI1 Diamond Measurements: 23.45 x 20.8 x 5.7mm Size: 6.25 Hallmark: 900 Plat Metal: Platinum Item #: BR-1949-070926-06
Diamond, Platinum
1.05 Carat Diamond Platinum Engagement Ring
Located in Hicksville, NY
Ring Size: 5 Metal Type: 900 Platinum [Tested & Hallmark] Weight: 2.9 grams Center Diamond Details Shape: Old European Brilliant Carat Weight: 1.05 carat Color: J Clarity: SI1 Fing...
White Diamond, Platinum
$1,916Sale Price|20% Off
Vintage Diamond Bridal Ring in Platinum
Located in Bloomington, MN
Vintage Diamond Bridal Ring in Platinum This vintage bridal ring is crafted in 900 platinum and features round diamonds set across the front in a classic prong-set design.
Diamond, Platinum
Vintage Platinum Scalloped .39ctw Diamond Eternity Band
Located in New York, NY
A scalloped silhouette gives this 900 platinum eternity band a graceful, softly architectural presence.
Diamond, Platinum
.90 Carat Diamond Platinum Engagement Ring
Located in Hicksville, NY
Item Details: Ring Size: 4 Metal Type: 900 PLATINUM [Hallmarked & Tested] Weight: 3 grams Center Diamond Details Shape: Old European Brilliant Carat Weight: .90 carat Color: J Cla...
White Diamond, Platinum
$6,172Sale Price|20% Off
Ballerina Opal & Diamond Ring in Platinum
Located in Bloomington, MN
Ballerina Opal & Diamond Ring in Platinum Crafted in 900 platinum, this ring features a prong-set Australian opal in a classic ballerina-style design.
Diamond, Opal, Platinum
Opal and Diamond Platinum Halo Ring
Located in New York, NY
Opal and Diamond Halo Ring 90% Platinum (stamped "PT 900") Ring size 10 Measurements: 29.68 x 21.91 x 23.70 - 2.44 mm Weight 12.5 grams Bright polish finish.
Diamond, Opal, Platinum
.35 Carat Diamond Platinum Engagement Ring
Located in Hicksville, NY
Item Details: Ring Size: 3.25 Metal Type: 900 PLATINUM [Tested & Hallmark] Weight: 2.4 grams Center Diamond Details Shape: Old European Brilliant Carat Weight: .35 carat Color: G C...
White Diamond, Platinum
0.42ctw Diamond Platinum Cross Pendant Fine Religious Jewelry
Located in McLeansville, NC
Gemstone Information: - Natural Diamonds - Total Carats - 0.42ctw Cut - Round Brilliant Color - F - H Clarity - I1 - I2 Metal: 900 Platinum (XRF tested) Weight: 2.2 Grams Stamps: ...
Diamond, Platinum
Platinum Marquise and Baguette Cut Diamond Earrings
Located in New York, NY
Length: 1.00 inch Markings: "PT.900" Metal: Platinum Weight: 20.3 grams Diamonds: 5.38 carats
Diamond, Platinum
Platinum graduated Diamond Tennis necklace 20 ct
Located in Zurich, Zollstrasse
Made in 900 platinum and ready to be worn. A total of 97 brilliant cut Diamonds with a total weight of 20 ct, H and I color, vs and si clarity.
Diamond, Platinum
Vintage Platinum Tahitian Pearl and Diamond Ring
Located in New York, NY
Weight: 5.3 Grams Stone: Tahitian Pearl & 0.36tcw Diamond Measurements: 28.2 x 19.2 x 8.55mm Size: 5.75 Hallmark: PT 900 Metal: Platinum Item #: BR-1812-022626-05
Diamond, Pearl, Platinum
Platinum 5.45ct Rubellite & .67ctw Diamond Halo Ring
Located in New York, NY
Weight: 14.6 Grams Stone: 5.45ct Rubellite, .67ctw Diamonds G SI1 Measurements: 16.1 x 23.5 x 8.9mm Size: 9 Hallmark: PT900 Metal: 900 Platinum Item #: BR-1832-031426-10
Diamond, Rubelite, Platinum
Platinum 1.94ct Tanzanite and Diamond Engagement Ring
Located in New York, NY
Weight: 6.2 Grams Stone: 1.94ct Tanzanite, 0.23tcw Diamond Measurements: 24 x 19.82 x 9mm Size: 5.5 Hallmark: PT 900 Metal: Platinum Item #: BR-1890-051926-14
Diamond, Tanzanite, Platinum
$2,553Sale Price|20% Off
Ornate Ruby & Diamond Milgrain Ring in Platinum
Located in Bloomington, MN
Ornate Ruby & Diamond Milgrain Ring in Platinum This ring is crafted in 900 platinum and features a 0.55ct red ruby set at the center of a wide, detailed band.
Diamond, Ruby, Platinum
Diamond Pendant Platinum Curved Trilliant Diamonds
Located in Stamford, CT
Platinum diamond pendant. 16 Inches long with 3 Inch extender. 4 curved trilliant H VS diamonds Approximate 1.00 carats Platinum Top to Bottom: 9.89mm Width: 9.99mm Depth or Thick...
Diamond, Platinum
$2,660Sale Price|20% Off
Tourmaline & Diamond By-Pass Ring in Platinum
Located in Bloomington, MN
Tourmaline & Diamond By-Pass Ring in Platinum This ring is crafted in 900 platinum and features a prong-set green tourmaline as the centerstone.
Diamond, Tourmaline, Platinum
$2,464Sale Price|20% Off
Pear Halo Emerald & Diamond Ring in Platinum
Located in Bloomington, MN
Pear Halo Emerald & Diamond Ring in Platinum Crafted in 900 platinum, this ring features a pear-shaped green emerald set in a prong setting and framed by a halo of round and mar...
Diamond, Emerald, Platinum
$5,852Sale Price|20% Off
Antique Sapphire & Diamond Shield Ring in Platinum
Located in Bloomington, MN
Antique Sapphire & Diamond Shield Ring in Platinum This antique ring is crafted in 900 platinum and features a striking shield-style design with bezel-set blue sapphires totalin...
Diamond, Sapphire, Platinum
$5,107Sale Price|20% Off
Vintage Opal & Diamond Cocktail Ring in Platinum
Located in Bloomington, MN
Vintage Opal & Diamond Cocktail Ring in Platinum This cocktail ring is crafted in 900 platinum and features a 4.53-carat oval cabochon Australian opal as the center stone.
Diamond, Opal, Platinum
Platinum 17.54ctw Round Diamond Riviera Bezel Graduated Tennis Necklace
Located in Houston, TX
Gender: Ladies Metal Type: 900 Platinum Length: 16.00 inches Width: 6.70 mm Weight: 54.50 grams Ladies 900 platinum single strand choker, diamond graduated link necklace.
Diamond, Platinum
$6,384Sale Price|20% Off
Antique Sapphire & Diamond Cocktail Ring in Platinum
Located in Bloomington, MN
Antique Sapphire & Diamond Cocktail Ring in Platinum This antique ring is crafted in 900 platinum and features bezel-set blue sapphires totaling 0.67ctw in a bold cocktail-style...
Diamond, Sapphire, Platinum
$3,724Sale Price|20% Off
Antique Ruby & Diamond Cocktail Ring in Platinum
Located in Bloomington, MN
Antique Ruby & Diamond Cocktail Ring in Platinum This antique cocktail ring is crafted in 900 platinum and features a circular ruby and diamond design with rich red rubies total...
Diamond, Ruby, Platinum
Platinum 0.96ct Round Chocolate Champagne Diamond Solitaire Pendant Necklace
Located in Houston, TX
Gender: Ladies Metal Type: 850 & 900 Platinum Length: 18.00 inches Width: 1.00 mm Weight: 5.41 grams Ladies 850 & 900 platinum single strand choker, diamond necklace.
Diamond, Platinum
$3,511Sale Price|20% Off
Antique Emerald & Diamond Shield Ring in Platinum
Located in Bloomington, MN
Antique Emerald & Diamond Shield Ring in Platinum This antique ring is crafted in 900 platinum and features green emeralds totaling 0.40ctw, arranged in a shield-style design wi...
Diamond, Emerald, Platinum
Platinum and 14k Yellow Gold Filigree Pin #24192
Located in Washington Depot, CT
XRF tested as 13.56k gold back 900 Platinum Top Weight: 3.5g/ 2.2dwt Size: 57.2mm X 7.7mm 3mm / 2.25" in length Very good condition and professionally polished.
14k Gold, Yellow Gold, Platinum
Heart Shaped Rubellite Platinum and Diamond Necklace
Located in Great Neck Plaza, NY
The dazzling diamond florets are meticulously pavé-set, creating a soft, radiant effect that enhances the vivid pink-red hue of the rubellites. Crafted in platinum and stamped PT 900...
Diamond, Rubelite, Platinum
$7,128Sale Price|20% Off
Antique Emerald & Diamond Shield Ring in Platinum
Located in Bloomington, MN
Antique Emerald & Diamond Shield Ring in Platinum This antique ring is crafted in 900 platinum and features a striking shield-style design with richly colored green emeralds tot...
Diamond, Emerald, Platinum
Modern Ruby and Platinum Line Bracelet, 8.90 Carats
Located in London, GB
A modern ruby and platinum line bracelet, channel set with a single row of French-cut rubies, in individually hinged links, with foliate engraved, openwork sides, with a box and tong...
Ruby, Platinum
Art Deco Platinum Bracelet with ca 13ct Diamonds
Located in Berlin, BE
An exceptional Art Deco bracelet crafted in 900 platinum, set with an impressive selection of high-quality diamonds totaling approximately 13 carats.
Diamond, Platinum
$4,256Sale Price|20% Off
Vintage Alexandrite & Diamond Double Halo Ring in Platinum
Located in Bloomington, MN
Vintage Alexandrite & Diamond Double Halo Ring in Platinum This vintage ring is crafted in 900 platinum and features a prong-set oval alexandrite weighing 0.85ct.
Alexandrite, Diamond, Platinum
Vintage Platinum Ruby Diamond Cluster Ring 1.60ct Oval Ruby
Located in Great Neck Plaza, NY
The ruby is framed by an elegant halo of mixed-cut diamonds, including 6 marquise-cut diamonds totaling approximately 0.56 carats and 10 round brilliant diamonds totaling approximate...
Diamond, Ruby, Platinum
$7,980Sale Price|20% Off
Antique Ruby & Diamond Scalloped Cross Ring in Platinum
Located in Bloomington, MN
Antique Ruby & Diamond Scalloped Cross Ring in Platinum This antique ring is crafted in 900 platinum and features a scalloped cross-style design with bezel-set red rubies totali...
Diamond, Ruby, Platinum
.70 Carat Diamond Filigree Art Deco Platinum Ring
Located in Stamford, CT
Crafted in luxurious platinum, the ring offers both durability and timeless beauty, while the delicate filigree detailing adds depth, texture, and character. 17 round diamonds, H VS...
Diamond, Platinum
$39,200Sale Price|20% Off
Vintage Platinum 23.07ctw GIA Diamond Statement Pendant Station Necklace
Located in Montclair, NJ
Total Carat Weight: 23.07 (approx.) Material: Solid .900 & .950 Platinum Total Weight: 49.47 Grams Overall Width: 45.3mm (1.78") Overall Height: 55.1mm (2.17") Thickness: 11.1m...
Diamond, Platinum
Timeless Elegance: Platinum Trilogy Sapphire & Diamond Ring
Located in München, DE
Together, they form the classic trilogy silhouette—symbolizing a couple’s shared past, vibrant present, and cherished future. Crafted from solid 900 platinum, the ring offers a luxu...
Diamond, Sapphire, Platinum
Michael B Platinum Marquise Diamond Halo Pendant Necklace 2.25ctw
Located in Newport Beach, CA
We are pleased to present this elegant Michael B marquise diamond pendant necklace, a refined and eye-catching design that beautifully combines classic shape with modern brilliance. ...
Diamond, Platinum
Platinum 3.50ct Star Sapphire and Diamond Baguette Halo
Located in New York, NY
Weight: 13.0 Grams Stone: 3.50ct Star Sapphire, 1.56tcw Diamond Measurements: 28.7 x 20.5 x 19.4mm Size: 5.5 Hallmark: PT 900 Metal: Platinum Item #: BR-1727-102325-07
Diamond, Star Sapphire, Platinum
.30 Carat Diamond Swirl Platinum Engagement Ring
Located in Stamford, CT
There are multiple stamps in the shank, we do not know the designer. 1 full cut diamond, approx. total weight .30cts, F, VS 19 full cut diamonds, approx. total weight .15cts, F, ...
Diamond, Platinum
Vintage Platinum Round Sapphire Diamond Shoulders Engagement Ring Size 5.5
Located in Montclair, NJ
.) - 0.95ctw (approx.) (4) Natural Genuine Diamonds - Single/Baguette Cut - Pave/ Bezel Set - Nice Brilliant White Diamonds - 0.10ctw (approx.) Material: 900+ Platinum - Stamped Pla...
Diamond, Sapphire, Platinum
Art Deco Platinum Ladies Wristwatch with Diamonds
Located in Toledo, OH
The case is marked 900 platinum. It has a 17 jewel movement, Alleman & Gisiger.
Platinum
Platinum 2.57ct Ceylon Deep Royal Blue Sapphire & Diamond Pendant
Located in New York, NY
A striking Art Deco–inspired pendant showcasing a richly saturated 2.57 carat deep royal blue sapphire, elegantly framed in luminous 900 platinum and accented with brilliant diamonds.
Diamond, Blue Sapphire, Platinum
Platinum 1.40ct Diamond and Ruby Ballerina Ring MF05-051826
By LB Exclusive
Located in Southampton, PA
Beneath the centerpiece, an unadorned 900 platinum band keeps the composition balanced.In estate condition, this Platinum 1.40 ct Diamond and 4.14 ct Ruby Ballerina Ring comes with a...
Diamond, Ruby, Platinum
$1,918Sale Price|20% Off
Platinum 1ctw Pave Fiery Diamond Eternity Wedding Stack Band Ring
Located in Montclair, NJ
--Stone(s):-- (26) Natural Genuine Diamonds - Round Brilliant Cut - Pave Set - Nice Fiery White Brilliant Diamonds Total Carat Weight: 1.0 (approx.) Material: Solid .900+ Platinum W...
Diamond, Platinum
Oval Signet Ring - 950 Platinum with Monogram Engraving
By Victor Mayer
Located in Pforzheim, DE
Reference: 51222/00/00/00/900 Material: Platinum 950PT Dimensions: approx. 14.0 x 11.0 mm Engraving: Mongram Ringsize: 56 This jewellery with engraving is available in stock and can ...
Platinum
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 rings, vintage engagement rings or Art Deco engagement rings.
Shop antique and vintage diamond rings, diamond necklaces and other extraordinary diamond jewelry on 1stDibs.
Ancient Egyptians referred to the vibrant stone as the “gem of the sun.”
There are many ways to showcase a diamond, from traditional prongs to a smooth, streamlined bezel. Here’s everything you need to consider.
The vintage bombé ring is bursting with color and timeless style.
Zircon is a magnificent and underrated natural gemstone that has been worn and adored for centuries.
Givers of fine gems enjoy surprise more than receivers, and women more than men. Find out what else our survey of 3,000 Americans revealed.
If diamonds don’t seem right, what about a magnificent sapphire, ruby or emerald?
Accounting for just 1 percent of all diamonds, these marvels of nature are exceedingly rare and gorgeously complex.
Learn about these antique jewelry styles, then choose a design that speaks to you.