Skip to main content

Asscher Cut Aquamarine

1
to
10
54
10
25
19
17
2
2
1
1
1
1
1
11
71
1
1
1
2
1
1
1
1
7
4
3
2
2
46
39
85
35
23
36
7
14
72
53
2
11
11
66
6
2
2
1
to
Sort By
1.43ct Asscher Cut Aquamarine Engagement Ring, Platinum
Located in New York, NY
A captivating platinum ring with a 1.43-carat Asscher-cut aquamarine, secured by double prongs. The
Category

21st Century and Contemporary Unknown Art Deco Engagement Rings

Materials

Aquamarine, Sapphire, Platinum

1.39ct Asscher Cut Aquamarine Engagement Ring, Platinum
Located in New York, NY
This stunning aquamarine engagement ring showcases a lively 1.39-carat Asscher cut aquamarine in a
Category

21st Century and Contemporary Unknown Art Deco Engagement Rings

Materials

Aquamarine, Diamond, Platinum

2.46ct Asscher Cut Aquamarine Eternity Wedding Band, Platinum
Located in New York, NY
A stunning wedding band with an eternity of Asscher cut aquamarines totaling 2.46 carats. The
Category

21st Century and Contemporary Unknown Art Deco Band Rings

Materials

Aquamarine, Platinum

0.84ct Asscher Cut Aquamarine Engagement Ring, Diamond Floral Halo, Platinum
Located in New York, NY
Platinum Floral Aquamarine Ring: Features a vibrant Asscher cut aquamarine with a floral halo of
Category

21st Century and Contemporary Unknown Art Deco Engagement Rings

Materials

Aquamarine, Diamond, Platinum

1.97ct Asscher Cut Aquamarine Engagement Ring, Diamond & Sapphire Halo, Platinum
Located in New York, NY
A platinum ring showcasing a 1.97-carat Asscher-cut aquamarine encircled by a dual halo. The first
Category

21st Century and Contemporary Unknown Art Deco Engagement Rings

Materials

Aquamarine, Diamond, Sapphire, Platinum

1.08ct Asscher Cut Aquamarine Engagement Ring, Diamond & Onyx Halo, Platinum
Located in New York, NY
This Art Deco-inspired ring showcases a 1.08-carat Asscher cut aquamarine, accented by onyx and a
Category

21st Century and Contemporary Unknown Art Deco Engagement Rings

Materials

Aquamarine, Diamond, Onyx, Platinum

1.05ct Asscher Cut Aquamarine Pendant, Sapphire & Diamond Halo, Platinum
Located in New York, NY
Presenting an exquisite platinum pendant showcasing a bezel-set, natural Asscher-cut aquamarine
Category

21st Century and Contemporary Unknown Art Deco Pendant Necklaces

Materials

Aquamarine, Diamond, Sapphire, Platinum

Art Deco Asscher Cut Aquamarine, Sapphire, & Diamond Ring in Platinum
Located in Boston, MA
carat Asscher cut Santa Maria aquamarine secured by four claw form prongs. Framed by six vivid blue
Category

Vintage 1930s Art Deco Fashion Rings

Materials

Aquamarine, Diamond, Sapphire, Platinum

1.00ct Asscher Cut Aquamarine Engagement Ring, Sapphire & Diamond Halo, Platinum
Located in New York, NY
A double halo aquamarine ring that features an approximately 1-carat Asscher-cut natural aquamarine
Category

21st Century and Contemporary Unknown Art Deco Engagement Rings

Materials

Aquamarine, Diamond, Sapphire, Platinum

Aquamarine and Diamond Halo Art Deco Style Engagement Ring in 18K White Gold
Located in Bangkok, TH
Showcases a central 2.5 carat Asscher cut aquamarine, this ring is crafted in 18k white gold with
Category

21st Century and Contemporary Thai Art Deco Engagement Rings

Materials

Aquamarine, Diamond, 18k Gold, White Gold

Authentic Aquamarine Gemstones 3.15 carats Asscher Cut Natural Pakistani Gem
Located in Bangkok, TH
Clean Shape Octagon Cut Asscher Discover a stunning collection of authentic Aquamarine gemstones
Category

21st Century and Contemporary Pakistani Modern Loose Gemstones

Materials

Aquamarine

Glamming 20.50 Carats Asscher Cut Natural Aquamarine Gemstone Pair for Earrings
Located in Bangkok, TH
30x Loupe, looks Loupe Clean. In pictures, there is the needle-like effect Shape Asscher Cut Dive
Category

21st Century and Contemporary Pakistani Modern Loose Gemstones

Materials

Aquamarine

Asscher Cut 4.30 Carat Natural Loose Aquamarine Square Shape Gems For Ring
Located in Peshawar, PK
. Aquamarine's versatility allows it to be fashioned into various cuts, from traditional emerald cuts to more
Category

21st Century and Contemporary Pakistani Arts and Crafts Loose Gemstones

Materials

Aquamarine

Amazing 4.15 Carats Natural Loose Unheated Aquamarine Asscher Cut Gem For Ring
Located in Peshawar, PK
. Aquamarine's versatility allows it to be fashioned into various cuts, from traditional emerald cuts to more
Category

21st Century and Contemporary Pakistani Arts and Crafts Loose Gemstones

Materials

Aquamarine

3.65 Cts Natural Light Aquamarine Loose Gemstone Asscher Cut From Pakistan Mine
Located in Peshawar, PK
Blue Shape: Asscher Certficate: On Customer Demand Treatment: Non . Aquamarine is a captivating
Category

Antique Early 1600s Pakistani Arts and Crafts Loose Gemstones

Materials

Aquamarine

Aquamarine Earrings Square Emerald Cut 4.83 Carats
By Merkaba
Located in Beverly Hills, CA
Pristine 4.83 carat square-octagon Aquamarine, platinum earrings, decorated with a pair of 0.38
Category

21st Century and Contemporary American Contemporary Drop Earrings

Materials

Aquamarine, Beryl, Diamond, White Diamond, Multi-gemstone, Platinum

Aquamarine Earrings 4.83 Carat Square Emerald Cut
By Merkaba
Located in Beverly Hills, CA
Pristine 4.83 carat square-octagon Aquamarine, platinum earrings, decorated with a pair of 0.38
Category

21st Century and Contemporary American Contemporary Drop Earrings

Materials

Aquamarine, Beryl, Diamond, White Diamond, Multi-gemstone, Platinum

Natural Sea Blue Aquamarine Stone 1.52 Carats Aquamarine Ring AquamarineNecklace
Located in Bangkok, TH
Blue Aquamarine Stone WEIGHT 1.52 carats DIMENSIONS 7.6 x 7.4 x 4.8 mm CLARITY SI SHAPE Square CUT
Category

21st Century and Contemporary Pakistani Modern Loose Gemstones

Materials

Aquamarine

23.88 Carat Intense Blue Ascher Aquamarine Natural Gemstone
By FERRUCCI
Located in New York, NY
23.88 carat Natural Blue Ascher cut Aquamarine gemstone, of a high quality intense blue
Category

2010s Cocktail Rings

Materials

Aquamarine

23.88 Carat Intense Blue Square Emerald Aquamarine Natural Gemstone
By FERRUCCI
Located in New York, NY
23.88 carat Natural Blue Square Emerald cut Aquamarine gemstone, of a high quality intense blue
Category

2010s Cocktail Rings

Materials

Aquamarine

Faye Kim Platinum Asscher Diamond Eternity Channel Ring
By Faye Kim
Located in Westport, CT
also show Platinum Asscher Diamond Eternity Bezel Ring and Platinum Aquamarine and Diamond Engagement
Category

2010s American Contemporary Band Rings

Materials

Diamond, Platinum

Aquamarine Diamond Platinum Ring
Located in Beverly Hills, CA
is accented by 8 perfect asscher-cut diamonds which are channel-set on the sides of the aquamarine
Category

21st Century and Contemporary American Cocktail Rings

Materials

Aquamarine, Diamond, Platinum

Fine Aquamarine Diamond Platinum Ring
Located in Beverly Hills, CA
color. It is accented by 8 asscher-cut diamonds channel-set on its sides and weighing 0.50 carats. The
Category

21st Century and Contemporary American Cocktail Rings

Materials

Aquamarine, Diamond, Platinum

LEYSER 18k White Gold Santa Maria Aquamarine Diamond Ring
By Thomas Leyser
Located in Idar-Oberstein, DE
18k White Gold Ring, set with: 1x Fine Aquamarine (fac., radiant-cut, Santa Maria, 12.8mm, 7.70
Category

21st Century and Contemporary German Contemporary Cocktail Rings

Materials

Aquamarine, Diamond, 18k Gold, White Gold

GIA Certified Blue 7.2 Carat Aquamarine Diamond 18 Karat Gold Ring
Located in Wallkill, NY
Stunning GIA Certified 18K White Gold Ring with center 7.20 Carat Aquamarine Stone. Square Asscher
Category

Vintage 1950s Unknown Solitaire Rings

Materials

Aquamarine, Diamond, 18k Gold, Gold, Yellow Gold

Faye Kim Platinum Aquamarine Diamond 3-Stone Ring
By Faye Kim
Located in Westport, CT
also show Platinum Aquamarine Diamond Ring stacked with Platinum Asscher Diamond Eternity Channel Ring
Category

2010s American Contemporary Cocktail Rings

Materials

Aquamarine, Diamond, Platinum

50ct Natural Garnet Tourmaline Aquamarine Peridot Citrine Topaz Diamond Necklace
Located in New York, NY
, Peridot, Citrine & Blue Topaz Square Asscher Cuts Clean Clarity & Transparent. 1.00ct round brilliant
Category

2010s American Chain Necklaces

Materials

Aquamarine, Citrine, Diamond, Garnet, Peridot, Topaz, Tourmaline, 14k Go...

FERRUCCI 23.88 Carat Intense Blue Aquamarine in 18k White Gold Diamond Ring
By FERRUCCI
Located in New York, NY
23.88 carat Natural Blue Ascher cut Aquamarine gemstone, of a high quality intense blue
Category

2010s American Art Nouveau Engagement Rings

Materials

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

Antique 71.50Ct Aquamarine 0.10Ct Diamond and Platinum Pendant Circa 1925
Located in Jesmond, Newcastle Upon Tyne
aquamarine is surmounted with impressive collet set 0.10ct Asscher-cut diamond, completing the pendant design
Category

Vintage 1920s Pendant Necklaces

Materials

Aquamarine, Diamond, Platinum

Vintage 7.53 Carat Aquamarine and Diamond Platinum Engagement Ring
Located in Jesmond, Newcastle Upon Tyne
feature four-claw set 7.53ct emerald cut aquamarine. The substantial setting is further embellished with
Category

1990s Unknown Cocktail Rings

Materials

Aquamarine, Diamond, Platinum

1960s, 15.32 Carat Aquamarine and Diamond Cocktail Ring in Platinum
Located in Atlanta, GA
platinum. It dates back to the 1960s and features Asscher cut accent diamonds. It has a very rich and
Category

Vintage 1960s Unknown Retro Cocktail Rings

Materials

Aquamarine, Diamond, Platinum

Art Deco Style Aquamarine with Sapphire and Diamond Halo Pendant in 14K Gold
Located in Bangkok, TH
: Aquamarine Shape: Asscher Cut Size: 6x6 mm. Number: 1 Weight: 1.00 Carat (approx. in total) Accent Gemstones
Category

21st Century and Contemporary Unknown Art Deco Pendant Necklaces

Materials

Aquamarine, Diamond, Sapphire, 14k Gold, White Gold

1.5 Ct. Aquamarine and Diamond Art Deco Style Engagement Ring in 14K White Gold
Located in Bangkok, TH
aquamarine is bezel set sitting atop a balanced dispersion of old cut diamonds that total 0.084 carat. This
Category

21st Century and Contemporary Thai Art Deco Engagement Rings

Materials

Aquamarine, Diamond, 14k Gold, White Gold

Tanzanite Earrings 4.03 Carat Square Octagon
By Merkaba
Located in Beverly Hills, CA
Striking pair of 4.03 carat total "Asscher cut" Tanzanite earrings decorated with a total of 1.16
Category

21st Century and Contemporary American Contemporary Drop Earrings

Materials

Diamond, White Diamond, Multi-gemstone, Tanzanite, Platinum

10.17 Carat Natural Aqua Ruby Diamond 14k Rose Gold Retro Art Deco Pendant
Located in Stamford, CT
weight 10.17cts, 14.1 x 11.9mm, natural untreated original Asscher cut Aqua 4 natural bright pinkish red
Category

Early 20th Century Art Deco Necklace Enhancers

Materials

Ruby, Aquamarine, Diamond, Gold, White Gold, 14k Gold, Rose Gold

DONNA VOCK Asscher Cut Aquamarine Diamond Ring
By Donna Vock
Located in NY, NY
A lady's favorite cocktail ring. Highest grade aquamarine set in a Diamond 18KW Gold ring. Size 6
Category

21st Century and Contemporary American Contemporary Cocktail Rings

Materials

Aquamarine, Diamond, 18k Gold

GIA Asscher Cut Diamond Engagement Ring Platinum 950
Located in Tarzana, CA
Center: 1 carat GIA Asscher cut Side Diamonds: 0.80 carat F VS round cut Total: 1.80 Carat
Category

21st Century and Contemporary American Modern Engagement Rings

Materials

Aquamarine, Diamond, Platinum

GIA Certified 5.50 Carat Large Asscher Cut Diamond Solitaire Ring in Platinum
Located in Orlando, Florida
GIA Certified 5.50 Carat Asscher Cut Natural Diamond Solitaire Ring in Platinum A Copy of the GIA
Category

21st Century and Contemporary American Modern Engagement Rings

Materials

Diamond, Platinum

GIA Certified Giant 5.06 Carat Asscher Cut Halo Diamond Sapphire Engagement Ring
Located in Orlando, Florida
GIA Certified Giant 5.06 Carat Asscher Cut Halo Diamond Sapphire Engagement Ring A stunning ring
Category

21st Century and Contemporary American Art Deco Engagement Rings

Materials

Sapphire, Blue Sapphire, Diamond, White Diamond, Gold, Platinum

Art Deco Style GIA Certified 5.28 Carat Asscher Cut Big Diamond Three-Stone Ring
Located in Orlando, Florida
Art Deco Style GIA Certified 5.28 carat Asscher Cut Big Diamond Three-Stone Ring GIA Certificate
Category

21st Century and Contemporary American Art Deco Engagement Rings

Materials

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

Cocktail 18k white gold ring with a 28 carats circa Aquamarine and 36 diamonds
Located in Roma, IT
A beautiful 23 carats circa aquamarine square asscher cut made in 18k white gold with 36 diamonds
Category

2010s Italian Contemporary Cocktail Rings

Materials

Aquamarine, White Diamond, 18k Gold

5 CTW. Aquamarine and Pink Sapphire Diamond Cocktail Ring
By carpenter and sons
Located in Aliso Viejo, CA
has a 3-carat stunning custom-cut Asscher Aquamarine. This stone contains a pure and clean blue color
Category

Early 2000s North American Modern Cocktail Rings

Materials

Aquamarine, Diamond, Pink Sapphire, 18k Gold, Rose Gold, Platinum

3 Carat Aquamarine Red Agate and Diamond Rose Gold Ring
By carpenter and sons
Located in Aliso Viejo, CA
A beautiful look inspired by modern design, this ring has a 3 carat aquamarine Asscher cut center
Category

Early 2000s American Modern Cocktail Rings

Materials

Agate, Aquamarine, Diamond, 18k Gold, Rose Gold, Silver

18 Karat White Gold 28, 4 Carat Aquamarine Cocktail Ring by Jochen Leën
By Jochen Leën
Located in Antwerp, BE
18 Karat White gold Cocktail Ring featuring a 28,4 carat Aquamarine stone. Assher cut measuring
Category

2010s Belgian Contemporary Cocktail Rings

Materials

Aquamarine, White Diamond, 18k Gold, White Gold

18K Gold 22.57 Carat Aquamarine and 1.76 TCW Diamonds Earrings
Located in New York, NY
COLOR ROUND CUT DIAMONDS: 0.90ct ASSCHER CUT DIAMONDS: 0.86ct DIAMOND COLOR: F DIAMOND CLARITY: VS2
Category

2010s American Art Nouveau Drop Earrings

Materials

Aquamarine, Diamond, 18k Gold

GIA Certified 1.52 Carat I VS1 Halo Diamond Engagement Ring in Platinum & Gold
Located in Orlando, Florida
- Certified - Diamond ◭ Primary Stone Color: I ◭ Primary Stone Clarity: VS1 ◭ Primary Stone Shape: Asscher Cut
Category

21st Century and Contemporary American Contemporary Engagement Rings

Materials

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

Lizunova Green Tourmaline and Diamond 18 Karat White Gold Ring
By Lizunova Fine Jewels
Located in Sydney, NSW
Sydney in 18 karat white gold, the ring is set with an asscher cut green tourmaline of breathtaking
Category

21st Century and Contemporary Australian Art Deco Engagement Rings

Materials

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

18k Gold Natural Emerald Diamond Art Deco Style Engagement Ring Bridal Ring
Located in Orlando, Florida
Stone Type: Natural - Mined - Certified - Emerald ◭ Grade: AAA Grade ◭ Primary Stone Shape: Asscher Cut
Category

21st Century and Contemporary American Art Deco Engagement Rings

Materials

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

18K Gold 4 Carat Certified Natural Emerald Minimalist Style Engagement Ring
Located in Orlando, Florida
Type: Natural - Mined - Certified - Emerald ◭ Grade : AAA Grade ◭ Primary Stone Shape: Assher Cut
Category

21st Century and Contemporary American Modern Engagement Rings

Materials

Emerald, 18k Gold, Gold, Yellow Gold

Art Deco Style 3.50ct Asscher Cut Aquamarine and Diamond Ring in Platinum
Located in Yorkshire, West Yorkshire
This absolutely stunning ring features a 3.50ct beautiful Asscher Cut Aquamarine. The Aquamarine
Category

21st Century and Contemporary British Art Deco Engagement Rings

Materials

Aquamarine, Diamond, Platinum

Certified 11.23 Cts Asscher Cut Aquamarine Diamond Ring, True Santa Maria Color
Located in Hong Kong, HK
cut Aquamarine has the very desirable Santa Maria color. It is also oversized at 11.23 cts with good
Category

2010s Contemporary Cocktail Rings

Materials

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

Tiffany & Co. 1940s 14K Gold Vintage Ruby and Aquamarine Tiffany Brooch
By Tiffany & Co.
Located in Los Angeles, CA
Asscher Cut Aquamarine, Approximately 5-6 Carats, 9 Round Burma Rubies Approximately 1.80 Carats. An
Category

Vintage 1940s American Art Deco Brooches

Materials

Aquamarine, Ruby, 14k Gold, Rose Gold, Yellow Gold

Aquamarine Ring Gem 35.68 Carat Asscher Cut Loose Gemstone
By Merkaba
Located in Beverly Hills, CA
Incredible 35.68 carat Asscher cut Aquamarine gem offered loose to a remarkable gemstone collector
Category

21st Century and Contemporary Mozambican Modern Cocktail Rings

Materials

Aquamarine, Beryl

Aquamarine Ring Gem 35.68 Carat Asscher Cut Loose Gemstone
Aquamarine Ring Gem 35.68 Carat Asscher Cut Loose Gemstone
Free Shipping
W 0.85 in D 0.48 in L 0.85 in
Decadent 11.21 Carat Diamond Asscher Aquamarine Chandelier 18K Choker Necklace
Located in Miami, FL
Asscher shaped Genuine Aquamarine the focal point and weighs appx. 43.48 Carats. Encrusting the chain
Category

Vintage 1980s Art Deco Pendant Necklaces

Materials

Aquamarine, Diamond, 18k Gold

Tanzanite Ring Gem 8.23 Carat Asscher Cut Loose Gemstone
By Merkaba
Located in Beverly Hills, CA
Superb 8.23 carat Tanzanite Asscher cut gem offered loose to a passionate gem collector. Returns
Category

21st Century and Contemporary Unknown Contemporary Cocktail Rings

Materials

Tanzanite

Brilliant Natural Loose Aquamarine Gemstone 1.60 Carats Aquamarine Rings
Located in Bangkok, TH
CLARITY: SI SHAPE: Octagon CUT: Asscher Cut LOCALITY: Madagascar TREATMENT: None CERTIFICATE: Available
Category

21st Century and Contemporary Malagasy Modern Loose Gemstones

Materials

Aquamarine

Faye Kim Platinum Asscher Diamond Eternity Ring
By Faye Kim
Located in Westport, CT
Photos also show Platinum Asscher Diamond Eternity Channel Ring, Platinum Aquamarine and Diamond
Category

2010s American Contemporary Band Rings

Materials

Diamond, Platinum

Antique Aquamarine Gold Solitaire Ring
Located in Beverly Hills, CA
One Antique Aquamarine Gold Solitaire Ring. Featuring one square step cut aquamarine of
Category

Vintage 1910s American Edwardian Solitaire Rings

Materials

Aquamarine, Gold, 14k Gold, Yellow Gold

Tiffany & Co. Aquamarine and Diamond Platinum Ring 8.34 Carat
By Tiffany & Co.
Located in London, GB
ascher cut aquamarine in a 4 claw setting with a weight of approximately 8.34ct, with a light blue hue
Category

21st Century and Contemporary Modern Cocktail Rings

Materials

Aquamarine, Diamond, Platinum

3 Ct Rare Santa Maria Aquamarine and Diamond 18K Ring
Located in Mill Valley, CA
perfect Santa Maria Aquamarine color of brilliant blue, and the cut is a beautiful Asscher cut. If you
Category

2010s American Modern Solitaire Rings

Materials

Aquamarine, 18k Gold

  • 1
Get Updated with New Arrivals
Save "Asscher Cut Aquamarine", and we’ll notify you when there are new listings in this category.

Asscher Cut Aquamarine For Sale on 1stDibs

Surely you’ll find the exact asscher cut aquamarine you’re seeking on 1stDibs — we’ve got a vast assortment for sale. Frequently made of gold, platinum and 18k gold, this item was constructed with great care. Our collection of these items for sale includes 7 vintage editions and 23 modern creations to choose from as well. Finding the perfect asscher cut aquamarine may mean sifting through those created during different time periods — you can find an early version that dates to the 20th 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 2 carat and 2.5 carat versions are of considerable interest. There have been many well-made iterations of the classic asscher cut aquamarine over the years, but those made by FERRUCCI, carpenter and sons and Faye Kim are often thought to be among the most beautiful. A asscher cut aquamarine of any era or style can lend versatility to your look, but a version featuring aquamarine, from our inventory of 24, is particularly popular. A asscher cut version of this piece has appeal, but there are also emerald cut and mixed cut versions for sale. Most of our asscher cut aquamarine for sale are for women, but there are 16 pieces available to browse for men.

How Much is a Asscher Cut Aquamarine?

The price for a asscher cut aquamarine starts at $140 and tops out at $58,500 with these rings, on average, selling for $6,609.
Questions About Asscher Cut Aquamarine
  • 1stDibs ExpertApril 5, 2022
    An asscher cut emerald has a higher crown, smaller table and larger step facets than a traditional emerald cut. Between the two cuts, the asscher cut emerald is more brilliant. Find a collection of expertly vetted gems from some of the world’s top sellers on 1stDibs.
    1stDibs ExpertApril 5, 2022
    An asscher cut is a type of step cut for a gemstone. It features large step facets with a small table and high crown, giving off a gorgeous brilliance. Asscher cuts are known for an “X” pattern that’s visible when you look straight down at the gem. Shop a collection of asscher cut emeralds and other gemstones on 1stDibs from some of the world’s top sellers.
  • 1stDibs ExpertFebruary 22, 2021
    Because Asscher cut diamonds are rarer than other cuts (less than 2% of diamonds cut), they are more expensive than other cuts. Per carat, an asscher will usually be 10% more expensive than other cuts.
  • 1stDibs ExpertApril 5, 2022
    No, a square emerald cut is not the same as an asscher cut. Although they have the same basic shape and are both step cuts that maximize clarity, the asscher cut shows off a sharper angle at the corners. Shop a wide variety of gemstone jewelry on 1stDibs.
  • 1stDibs ExpertApril 5, 2022
    An Asscher cut diamond ring is one that has a central stone with a square shape and a stepped cut. Its high crown and deep pavilion give the diamond a brilliant sparkling appearance. Shop a variety of Asscher cut diamond gemstone rings on 1stDibs.