Old Diamonds
to
1,947
29,865
20,957
16,351
11,347
7,348
44,955
6,428
5,124
3,681
3,159
260
9,406
32,144
4,438
3,505
3,325
6,752
3,947
1,290
1,082
391
303
210
176
229
28,668
17,820
388
16503
7915
3214
1348
948
to
76
1
369
350
194
112
106
15,244
8,264
5,395
1,457
1,320
951
837
495
234
155
79
20
20
7
5
5
4
4
46,784
92
27,981
17,415
Sort By
Art Deco Old European Diamond Platinum Vintage Orange Blossom Engagement Ring
Located in Philadelphia, PA
Centering an old European cut diamond weighing approximately 0.42 carat - H color with VS2 clarity
Category
Vintage 1930s Art Deco Engagement Rings
Materials
Diamond, Platinum
1900s Edwardian 14K Yellow Gold Old European Diamond Ring
Located in Hicksville, NY
Tested]
Weight: 2.7 grams
Diamond Details: .90ct total weight, Old European Brilliant, J Color, SI
Category
Antique Early 1900s Edwardian Engagement Rings
Materials
Diamond, Gold, 14k Gold, Yellow Gold
GIA Certified 3 Carat Old Mine Cushion Diamond Platinum Studs
By Antinori Fine Jewels
Located in Chicago, IL
an exquisite pair of GIA certified 3 carat old mine cut cushion diamond platinum studs
full of
Category
2010s Italian Modern Clip-on Earrings
Materials
Diamond, White Diamond, Platinum
$28,000 Sale Price
20% Off
4.63ct Old Mine Brilliant Cut Diamond Ring with Pear Shape Shoulders
By Hancocks
Located in London, GB
A stunning old cut diamond ring by Hancocks, set to the centre with a beautifully bright and lively
Category
21st Century and Contemporary Engagement Rings
Materials
White Diamond
Art-Deco Platinum Ring with Old-Cut Diamonds — 1920s Elegance
Located in MONTMORENCY, FR
of the 1910s–1920s period. The elongated octagonal pavé top is set with multiple old-cut diamonds
Category
Early 20th Century French Art Deco Cocktail Rings
Materials
Diamond, Platinum
Antique Platinum 3.52ct Old European Cut Accented Diamond Engagement Ring
Located in Houston, TX
: 9.89 grams
One ladies Platinum antique diamond engagement accented ring with a half-round shank. The
Category
Early 20th Century Unknown Engagement Rings
Materials
Diamond, Platinum
Antique Art Deco Platinum Old European Diamond Engagement Ring
Located in Great Neck, NY
Beautiful Antique Art Deco Platinum Old European Diamond Engagement Ring. This beautiful antique
Category
Vintage 1920s Art Deco Engagement Rings
Materials
Diamond, Blue Sapphire, Platinum
1.74 Carat Old European Cut K-VS1 Diamond Platinum Wedding Ring
Located in New York, NY
Title:
1.74 Carat Old European Cut K-VS1 Diamond Platinum Wedding Ring
Style:
Wedding
Metal
Category
20th Century Wedding Rings
Materials
Diamond, Platinum
Antique Art Deco Platinum Old European Cut Diamond Engagement Ring
Located in Great Neck, NY
Beautiful Antique Art Deco Platinum Old European Cut Diamond Engagement Ring. This classic Art Deco
Category
Vintage 1930s Art Deco Engagement Rings
Materials
Diamond, Platinum
Circa 1890s Old Miner Diamond and Enamel Engagement Ring
Located in Hicksville, NY
Circa 1890s Old Miner Diamond and Enamel Engagement Ring - VEG#44a
Item Details:
Year: 1890S
Ring
Category
Antique 1890s Victorian Engagement Rings
Materials
Diamond, Gold, 14k Gold, Yellow Gold, Enamel
Victorian Long Old-Mine Cut Diamond Earrings, circa 1890s
Located in Idar-Oberstein, DE
A beautiful pair of Victorian Diamond Earrings from the 1890s, studded with old-mine cushion cut
Category
Antique Late 19th Century Unknown Victorian Dangle Earrings
Materials
Diamond, Gold, Silver
Antique Edwardian Platinum Old Cut Diamond Filigree Dome Cocktail Ring
Located in Great Neck, NY
Beautiful Antique Edwardian Platinum Old Cut Diamond Filigree Dome Cocktail Ring. This beautiful
Category
Vintage 1920s Art Deco Dome Rings
Materials
Diamond, Platinum
1.89 Carat Old European Cut L VVS2 Diamond Platinum Engagement Ring
Located in New York, NY
Title:
1.89 Carat Old European Cut L VVS2 Diamond Platinum Engagement Ring
Style:
Engagement
Metal
Category
20th Century Engagement Rings
Materials
Diamond, Platinum
Antique Old Mine Cut Diamond Emerald Ruby Gold Pendant
Located in Cairo, EG
natural green emerald stone with a diameter of 7.7mm×6.65mm and 2 old mine cut diamonds each with a
Category
Vintage 1910s Unknown Pendant Necklaces
Materials
Diamond, Emerald, Ruby, 14k Gold
1.16 Carat Old European Cut I SI2 Diamond Platinum Wedding Ring
Located in New York, NY
Title:
1.16 Carat Old European Cut I SI2 Diamond Platinum Wedding Ring
Style:
Wedding
Metal
Category
20th Century Wedding Rings
Materials
Diamond, Platinum
1.25 Carat Old European Cut K SI2 Diamond Platinum Engagement Ring
Located in New York, NY
Title:
1.25 Carat Old European Cut K SI2 Diamond Platinum Engagement Ring
Style:
Engagement
Metal
Category
20th Century Engagement Rings
Materials
Diamond, Platinum
Antique 1879 Victorian Japonesque-Style Floral Old Mine Cut Diamond Gold Brooch
Located in Santa Monica, CA
with one stunning old mine cut diamond at center. Crafted in multi-color 14k gold.
- 0.15 carat old
Category
Antique 1870s Victorian Brooches
Materials
Diamond, Gold
Edardian 1.80 Ct Old Mine Cut Diamond Pendant Necklace Platinum
Located in Napoli, IT
tested, chain marked
Pendant is centered by .40 old mine cut Diamond H/VS with 18 more old mine cut
Category
Antique Early 1900s European Edwardian Pendant Necklaces
Materials
Diamond, Platinum
Art Deco Platinum Old European Diamond Antique Necklace Dangling Briolette 1.6ct
By Estate Jewelry
Located in Brambleton, US
Art Deco Platinum Old European Diamond Antique Necklace Dangling Briolette 1.6ct
This is a
Category
20th Century Art Deco Drop Necklaces
Materials
Diamond, Platinum
Old Mine Fancy Yellow Diamond Drop Earrings, circa 1910
Located in London, GB
Old mine fancy yellow diamond drop earrings. A matching pair of earrings set to bottom with a
Category
Vintage 1910s Edwardian Dangle Earrings
Materials
Yellow Diamond, Yellow Gold, Platinum
1.59 Carat Circular Brilliant and Old European Diamond Platinum Engagement Ring
Located in New York, NY
Title:
1.59 Carat Circular Brilliant Cut I I1 and Old European Cut I SI1 Diamond Platinum
Category
20th Century Engagement Rings
Materials
Diamond, Platinum
1920s Antique Old European Cut Diamond Ring in Platinum
Located in New York, NY
1920s Antique Old european cut diamond engagement ring in platinum.
The details are as follows
Category
Vintage 1920s American Engagement Rings
Materials
Diamond, Platinum
GIA Certified 2.68 Carat Old Euro Cut Diamond Stud Earrings
Located in Miami, FL
GIA certified old European cut natural diamond stud earrings in 14K yellow gold featuring 2.68
Category
21st Century and Contemporary American Modern Stud Earrings
Materials
Diamond, Yellow Gold
French old mine diamond 18k yellow gold engagement ring
Located in Beverly Hills, CA
old mine cut diamond, L color, SI2 clarity, accented by eight single-cut diamonds totaling
Category
Vintage 1920s Modern Engagement Rings
Materials
Diamond, Gold, 18k Gold, Yellow Gold, Platinum
Antique Art Deco Platinum Old Mine Diamond Engagement Ring - GIA
Located in Great Neck, NY
Beautiful Antique Art Deco Platinum Old Mine Diamond Engagement Ring - GIA. This incredible Art
Category
Vintage 1920s Art Deco Engagement Rings
Materials
Diamond, Platinum
1.17 Carat Old Mine Cut Diamond Solitaire Gypsy Engagement Ring
Located in Santa Monica, CA
A bold solitaire gypsy engagement ring with a 1.17 carat old mine cut diamond from the estate fine
Category
20th Century Solitaire Rings
Materials
Diamond, Gold, 14k Gold, White Gold
1.42 Carat Old European Cut K-VS1 Diamond Platinum Wedding Ring
Located in New York, NY
Title:
1.42 Carat Old European Cut K-VS1 Diamond Platinum Wedding Ring
Style:
Wedding
Metal
Category
20th Century Wedding Rings
Materials
Diamond, Platinum
Antique 14k Gold Russian Old Mine Cut Diamond Earrings
Located in Firenze, FI
Antique earring in floral shape with old mine cut diamonds centered with 1 larger old mine diamond
Category
Mid-20th Century Russian Art Deco Clip-on Earrings
Materials
Diamond, 14k Gold
Antique Platinum Ring with Old European-cut Center
Diamond Accents - Size 5.75
Located in Scottsdale, AZ
Antique Platinum Ring with One ~1ct 6.5mm SI1/J Central Old European-Cut Diamond
Twenty Round
Category
20th Century Fashion Rings
Materials
Diamond, Platinum
EGL Certified 3.35 Carat Old European Diamond Platinum Stud Earrings
Located in Stamford, CT
Well matched Old European cut diamond stud earrings. 2, EGL certified I-J (near colorless) round
Category
21st Century and Contemporary Stud Earrings
Materials
Diamond, Platinum
Circa 1900s GIA Fancy Brown Old European Brilliant Diamond Engagement Ring
Located in Hicksville, NY
Circa 1900s GIA Fancy Brown Old European Brilliant Diamond Engagement Ring - VEG#43b
Item Details
Category
Antique Early 1900s Engagement Rings
Materials
Brown Diamond, Platinum
Vintage 1.70 Carat Old European Cut Diamond Platinum Engagement Ring
Located in Chicago, IL
Vintage 1.70 Carat Old European Cut Diamond Platinum Engagement Ring
A beautiful vintage
Category
Vintage 1940s American Art Deco Engagement Rings
Materials
Diamond, White Diamond, Platinum
$20,000 Sale Price
20% Off
Yellow Gold Diamond Vintage Solitaire Engagement Ring 14k Old Mine
Located in Greensboro, NC
: 14k Yellow Gold & 14k White Gold
Stone Information
Natural Diamond
Carat(s): .08ct
Cut: Old Mine
Category
21st Century and Contemporary Engagement Rings
Materials
Diamond, 14k Gold, Yellow Gold
Circa 1900s GIA .68ct Old European Diamond Engagement Ring
Located in Hicksville, NY
: 3.9 grams
Center Diamond Details:
GIA Report#: 1236394536
Weight: .68ct total weight
Cut: Old
Category
Early 20th Century Engagement Rings
Materials
Diamond, Gold, 14k Gold, Yellow Gold
Retro Platinum Old European Cut Diamond Architectural Ring, 3 Carats
Located in Miami, FL
. Featuring approximately 3.00 carats of Old European cut diamonds, the ring showcases an architectural
Category
Early 20th Century Art Deco Cocktail Rings
Materials
Diamond, Platinum
Victorian rose gold and old mine cut diamond flower bracelet
Located in PARIS, FR
featuring a movable flower at its center. The petals are set with rose-cut diamonds and centered with an Old
Category
Antique Late 19th Century Victorian Bangles
Materials
Diamond, Rose Gold, Silver
Antique Art Deco Platinum Old European Diamond Engagement Ring
Located in Great Neck, NY
Beautiful Antique Art Deco Platinum Old European Diamond Engagement Ring. This classic engagement
Category
Vintage 1920s Unknown Art Deco Engagement Rings
Materials
Diamond, Platinum
Edwardian 2.05 Carat Old European Cut Diamond Engagement Ring GIA
Located in Montgomery, AL
We are loving this filigree solitaire engagement ring!!
The best part?
The spread of the diamond
Category
Early 20th Century Edwardian Engagement Rings
Materials
Diamond, Platinum
Antique Circa 1900s 14k Gold Natural Old Cut Diamond Solitaire Earring
Located in Fatih/İstanbul, 34
In very good condition.
Total weight is 3.1 grams.
Totally is diamond 0.80 ct.
The diamond is has
Category
Antique Early 1900s Victorian Lever-Back Earrings
Materials
Diamond, 14k Gold
1.53 Carat Old European Cut O VS2 Diamond Platinum Engagement Ring
Located in New York, NY
Title:
1.53 Carat Old European Cut O VS2 Diamond Platinum Engagement Ring
Style:
Engagement
Category
20th Century Engagement Rings
Materials
Diamond, Platinum
Victorian old European cut diamond 18k yellow gold snake ring
Located in Beverly Hills, CA
This evocative Victorian snake ring coils gracefully around the finger, crowned with a glowing Old
Category
Antique 1880s Victorian Cocktail Rings
Materials
Diamond, Gold, 18k Gold, Yellow Gold
Antique Platinum and Yellow Gold Old European Diamond Bar Pin
Located in Coral Gables, FL
Antique platinum-topped bar pin featuring 10 Old European cut diamonds of VS clarity and G/H color
Category
Antique Late 19th Century Brooches
Materials
Diamond, Yellow Gold, Platinum
Old European Cut Diamond Ring .90ct Platinum 1.08ct TDW Vintage Engagement
By Estate Jewelry
Located in East Brunswick, NJ
This lovely vintage ring is crafted in solid luxurious Platinum.
The center old European cut
Category
Vintage 1960s Bridal Rings
Materials
Diamond, Platinum
Edwardian, Platinum
Old European Cut Diamond Lavalier Necklace
Located in Brisbane City, QLD
Old European cut diamonds each set in a round setting of platinum hanging from an articulated bale
Category
Early 20th Century Art Nouveau Pendant Necklaces
Materials
Diamond, Gold, 14k Gold, White Gold, Platinum
Edwardian 1.30 CTW Old European Diamond Platinum Antique Foliate Engagement Ring
Located in Philadelphia, PA
Centering an old European cut diamond weighing approximately 1.10 carats
K color with VS2 clarity
Category
Vintage 1930s Edwardian Engagement Rings
Materials
Diamond, Platinum
1.82 Carat Old European Cut and Baguette Diamond Platinum Vintage Ring
Located in New York, NY
Title:
1.82 Carat Old European Cut O VS2 and Baguette Shape K VS1 Diamond Platinum Vintage Ring
Category
20th Century Engagement Rings
Materials
Diamond, Platinum
Vintage Art Deco Platinum Old European
Rose Cut Diamond Ring
Located in Montgomery, AL
following gemstones
1 - 5.96mm X 3.36mm Old European Cut Diamond; LM Color; SI Clarity; Estimated Weight
Category
Early 20th Century Art Deco Fashion Rings
Materials
Diamond, Pink Diamond, Platinum
Old Mine Cut Diamond Onyx Yellow Gold 18k Ring
Located in Geneva, CH
Old mine cut Diamond Onyx Yellow Gold 18K Ring.
Diamond central round old mine cut: approximately
Category
Vintage 1980s European Retro Fashion Rings
Materials
Diamond, Onyx, 18k Gold, Yellow Gold
Antique Edwardian Platinum Old Cut Diamond Milgrain Engraved Engagement Ring
Located in Montclair, NJ
--Stone(s):--
(1) Natural Genuine Diamond - Old Mine Cut - Prong Set - I Color - SI2 Clarity
Category
Antique Early 1900s Edwardian Cocktail Rings
Materials
Diamond, Platinum
1.48 Carat Old European Cut and Black Diamond Platinum Vintage Ring
Located in New York, NY
Title:
1.48 Carat Old European Cut Diamond Platinum Vintage Ring
Style:
Vintage
Metal:
Platinum
Category
20th Century Engagement Rings
Materials
Diamond, Platinum
Edwardian 1.25 Carats Old Mine Diamond Platinum Scrolled Engagement Ring
Located in Philadelphia, PA
old mine cut diamond weighing 0.95 carat - J color with VS2 clarity. With single cut diamond accents
Category
Vintage 1910s Edwardian Engagement Rings
Materials
Diamond, White Diamond, Platinum
Circa 1920s Art Deco Platinum Ornate Old European Diamond Ring
Located in Hicksville, NY
]
Weight: 5.6 grams
Note: Incredible details and engraving work. In pristine condition.
Diamond Details
Category
Vintage 1920s Art Deco Engagement Rings
Materials
Diamond, Platinum
Antique Classic Platinum 0.76ctw Old European Cut Diamond Basket Stud Earrings
Located in Montclair, NJ
--Stone(s):--
(2) Natural Genuine Diamonds - Old European Cut - Prong Set - H/I Color - VS2 Clarity
Category
21st Century and Contemporary Stud Earrings
Materials
Diamond, Platinum
Art Nouveau Golden Old Cut Diamond Ring, circa 1900s.
Located in Chorzów, PL
Art Nouveau ring made of gold and silver elements with diamonds in old rose and old-brilliant cuts
Category
Early 20th Century Unknown Art Nouveau Cocktail Rings
Materials
Diamond, 14k Gold, Silver
Antique Old European Cut Diamond Ring, circa Early 1900s
Located in San Francisco, CA
phenomenal Old European Cut Diamond at it's center, weighing approximately 1.50 carats. The stone (and entire
Category
Early 20th Century Unknown Art Deco Engagement Rings
Materials
Diamond, Platinum
Antique Old Cut Diamond Gold Half Hoop Bangle Bracelet
Located in Firenze, IT
18 kt gold diamond-bangle , approx. 1860ca very fine workmanship, head part. silver, curved
Category
Antique 1860s Italian Bangles
Materials
Diamond, Yellow Gold, Gold, 18k Gold
French Art Deco Platinum Ring with Old Cut Diamonds
Located in Brisbane City, QLD
carat. Flanking this central stone are two further Old European cut diamonds which each weigh 0.15 carat
Category
Early 20th Century French Art Deco Engagement Rings
Materials
Diamond, Platinum
- 1
- ...
Get Updated with New Arrivals
Save "Old Diamonds", and we’ll notify you when there are new listings in this category.
Old Diamonds For Sale on 1stDibs
On 1stDibs, there are many options to choose from in our inventory of old diamonds. Frequently made of Gold, Platinum and 18k Gold, these items were constructed with great care. Find a collection of 12759 vintage versions or 1437 modern creations for a more contemporary example of these cherished accessories. Our collection, which features older pieces for sale from the 18th Century and newer versions made as recently as the 21st Century, has proven very popular over the years. Pieces in our collection of old diamonds made by Art Deco jewelers — as well as those associated with Victorian — are very popular. There have been many well-made iterations of these items over the years, but those made by Single Stone, Hancocks and Mark Broumand are often thought to be among the most beautiful. There are many old european cut, old mine cut and round cut old diamonds for sale. There aren’t many items for men in our collection of old diamonds, as most of the options available are for women.
How Much are Old Diamonds?
Prices for old diamonds can differ depending upon size, time period and other attributes — at 1stDibs, these accessories begin at $27 and can go as high as $1,750,000, while old diamonds, on average, fetch $6,014.
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 rings, vintage engagement rings or Art Deco engagement rings.
Shop antique and vintage diamond rings, diamond necklaces and other extraordinary diamond jewelry on 1stDibs.
Questions About Old Diamonds
- 1stDibs ExpertMay 5, 2023How old an old European-cut diamond is varies. The old European cut is a precursor to the modern round brilliant cut. The stone appears circular when looked at from the top (because of its low table or largest facet) and has a high crown (the part above the middle of the stone) with larger facets. The tip of the stone, or the culet, is flat instead of pointed. This style was used predominantly in the 19th century, hence the name. It is best to consult a certified appraiser for assistance with dating and identifying antique jewelry. On 1stDibs, find a variety of European-cut diamond jewelry.
- What is an old European diamond?1 Answer1stDibs ExpertApril 5, 2022An old European diamond is one that features an Old European gemstone cut. This type of cut became popular during the Art Deco period and has a round shape with 58 central facets. You'll find a variety of European cut diamond gemstone jewelry on 1stDibs.
- How old are mine cut diamonds?1 Answer1stDibs ExpertApril 5, 2022Mine cut diamonds are up to 300 years ago. Mine cut diamonds were popular around the 18th century during Victorian times and are still in high demand today. You’ll find a wide selection of mine cut diamond jewelry on 1stDibs.
- 1stDibs ExpertFebruary 22, 2021Although old European cut diamonds are often priced lower than modern cuts, due to scarcity, they can sometimes be more valuable than modern cut diamonds.
- 1stDibs ExpertApril 5, 2022Jewelry makers stopped using the old European cut for diamond and other gemstone jewelry around 1930. The style was common during the Art Deco period, but the brilliant cut became popular in the years that followed. On 1stDibs, shop a selection of Old European cut diamond gemstone jewelry.
- 1stDibs ExpertFebruary 22, 2021Because the old mine cut is no longer used on diamonds, diamonds with this cut are rare and so you can often get quite a lot of money for them. Nevertheless, it is still dependent on the quality of the individual diamonds and on the color, clarity, cut and carat number.
- 1stDibs ExpertAugust 24, 2021Yes, old European cut diamonds can be worth more than many other cut diamonds as they are not produced anymore. This cut was developed and popularized between the years 1890 and 1930 and is likely to be found in an antique ring belonging to this period and featuring a round-cut diamond.
- 1stDibs ExpertFebruary 22, 2021Old mine cut diamonds are usually worth less than old european cut diamonds. Because they are generally 10-15% less expensive, they are often larger than other cut diamonds for engagement rings.
Roman Malakov DiamondsMarch 22, 2021Like any other diamond, an old mine cut diamond's worth depends on a variety of factors. These factors include the 4C's (color, clarity, cut, carat), the overall beauty and "make" of the stone, the demand, supply, etc. On average however, old mine cuts are typically priced slightly lower (around 5-10%) than modern cut diamonds.
More Ways To Browse
Faberge Silver Brooch
Chanel Hammered Gold Earrings
Chanel Heart Pearl Earrings
Chanel No 5 Charm
Chanel Perfume Chain
Chanel Starfish
Chanel White Camelia Earrings
Charm Bracelet Gold 1970s
Chaumet Malachite
Cheetah Earrings
Chinese Cloisonne Necklace
Chopard Butterfly
Chopard Happy Brooch
Chrome Hearts Chain
Ciner Enamel Bracelet
Ciner Leopard
Clear Crystal Drop Earrings
Cloisonne Bangle