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Buy Onyx Gemstones

(13)
Gem Type Weight Size Clarity Price Origin
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Black Onyx Gem - 12.3ct Baguette Facet (ID: 601530)

Baguette Black Onyx

12.28 ct (total 24.55ctw)
18 x 10 mm
$ 12.28
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Black Onyx Gem - 3.5ct Shield Faceted (ID: 602020)

Fancy Black Onyx

3.47 ct (total 6.94ctw)
15.5 x 11.6 mm
$ 3.47
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Black Onyx Gem - 12.1ct Octagon Step Cut (ID: 601982)

Octagon / Emerald Cut Black Onyx

12.13 ct (total 24.26ctw)
18 x 10 mm
$ 12.13
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Black Onyx Gem - 12.7ct Octagon Step Cut (ID: 601985)

Octagon / Emerald Cut Black Onyx

12.71 ct (total 25.41ctw)
18.1 x 9.9 mm
$ 12.71
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Black Onyx Gem - 3.2ct Shield Faceted (ID: 602250)

Fancy Black Onyx

3.21 ct (total 6.41ctw)
15.4 x 11.5 mm
$ 3.21
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Black Onyx Gem - 12.5ct Octagon Step Cut (ID: 601974)

Octagon / Emerald Cut Black Onyx

12.48 ct (total 24.96ctw)
18.1 x 10.1 mm
$ 12.48
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Black Onyx Gem - 3.3ct Shield Faceted (ID: 602018)

Fancy Black Onyx

3.30 ct (total 6.59ctw)
15.4 x 11.7 mm
$ 3.30
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Black Onyx Gem - 12ct Octagon Step Cut (ID: 601984)

Octagon / Emerald Cut Black Onyx

12.01 ct (total 24.01ctw)
17.9 x 9.9 mm
$ 12.01
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Black Onyx Gem - 3.3ct Shield Faceted (ID: 602015)

Fancy Black Onyx

3.29 ct (total 6.58ctw)
15.5 x 11.6 mm
$ 3.29
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Black Onyx Gem - 2.8ct Shield Faceted (ID: 602021)

Fancy Black Onyx

2.8ct
15.4 x 11.6 mm
$ 1.41
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Black Onyx Gem - 12.3ct Baguette Facet (ID: 601521)

Baguette Black Onyx

12.32 ct (total 24.64ctw)
7.8 x 9.9 mm
$ 12.32
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Black Onyx Gem - 12.5ct Baguette Facet (ID: 601527)

Baguette Black Onyx

12.48 ct (total 24.96ctw)
18.1 x 10.1 mm
$ 12.48
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Black Onyx Gem - 11.8ct Baguette Facet (ID: 601526)

Baguette Black Onyx

11.75 ct (total 23.50ctw)
18 x 10.1 mm
$ 11.75
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About Onyx

Onyx is the black form of chalcedony, a cryptocrystalline form of quartz. Onyx naturally occurs in bands of black and white, and is typically dyed to produce the familiar jet black cabochons.
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Found exactly what I was looking for, but I don't know how to tell the size. I'll have my jeweler nake it fit.
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Overall Rating -> 10 star ratings
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Posted By Joe in November, 2020
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Overall Rating -> 10 star ratings
I was able to find a gemstone that my sister is been looking for for a few years now in under a minute and Had quite a selection to choose from
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83
More Shapes
  • Asscher Cut
  • Baguette / Scissor Cut
  • Baguette Cabochon
  • Baguette Checkerboard
  • Baguette Crystal Cluster
  • Baguette Facet
  • Baguette Rose-Cut
  • Baguette Step Cut
  • Baguette Sugarloaf Cabochon
  • Ball Facet
  • Baroque
  • Barrel
  • Barrel / Checkerboard
  • Barrel / Full-Round
  • Barrel / Scissor Cut
  • Barrel Cabochon
  • Barrel Rose Cut
  • Bear Carving with Hole
  • Bird Carving
  • Briolette
  • Briolette with Hole
  • Bullet Shape Checkerboard
  • Carved
  • Carved Baguette
  • Carved Bird
  • Carved Cameo
  • Carved Chameleon
  • Carved Cushion
  • Carved Elephant
  • Carved Fancy
  • Carved Fish
  • Carved Fish with Hole
  • Carved Flower
  • Carved Fruit
  • Carved Half Heart
  • Carved Heart
  • Carved Heart Cabochon
  • Carved Leaf
  • Carved Marquise
  • Carved Marquise Cabochon
  • Carved Octagon
  • Carved Oval
  • Carved Oval Cabochon
  • Carved Pear
  • Carved Pear Cabochon
  • Carved Rhomb
  • Carved Rose
  • Carved Rose with Half Drilled Hole
  • Carved Round
  • Carved Round Bar
  • Carved Round Cabochon
  • Carved Sheep
  • Carved Shell
  • Carved Square
  • Carved Teardrop
  • Carved Trillion
  • Carved Turtle
  • Cushion Buff-Top
  • Cushion Cabochon
  • Cushion Carved Medusa Cameo
  • Cushion Checkerboard
  • Cushion Checkerboard (double sided)
  • Cushion Concave Fantasy Cut
  • Cushion Crystal Cluster
  • Cushion Mixed Cut
  • Cushion Rose-Cut
  • Cushion Shape Sugarloaf Cabochon
  • Cushion Sugarloaf Cabochon
  • Cushion-Cut
  • Diamond-Cut
  • Drilled Faceted Sphere
  • Drilled Sphere
  • Drilled Square Rondelle
  • Drilled Square Rondelle Slice
  • Fancy Bicone
  • Fancy Cabochon
  • Fancy Carved Cushion
  • Fancy Carved Oval
  • Fancy Carved Pear
  • Fancy Carved Round
  • Fancy Carved Trillion
  • Fancy Carving
  • Fancy Concave Cut
  • Fancy Crystal Cluster
  • Fancy Cut
  • Fancy Facet
  • Fancy Fantasy Carving
  • Fancy Slice
  • Fancy Star Facet
  • Fancy-Cut
  • Fantasy Carved Flower
  • Fantasy Carved Flower Cut
  • Fantasy Carved Leaf
  • Flower Carving
  • Flower-Cut
  • Half Heart Cabochon
  • Half Heart Facet
  • Half Moon Cabochon
  • Half Moon Facet-Cut
  • Half Moon Faceted
  • Half-Drilled Briolette
  • Half-Drilled Heart Facet
  • Half-Drilled Sphere
  • Heart Buff-Top
  • Heart Cabochon
  • Heart Cabochon with Hole
  • Heart Checkerboard (double sided)
  • Heart Facet
  • Heart Rose-Cut
  • Hexagon Cut
  • Marquise Cabochon
  • Marquise Checkerboard
  • Marquise Checkerboard (double sided)
  • Marquise Concave Cut
  • Marquise Facet
  • Marquise Mixed Cut
  • Marquise Slice
  • Marquise Sugarloaf Cabochon
  • Octagon / Scissor Cut
  • Octagon Buff-Top
  • Octagon Cabochon
  • Octagon Checkerboard
  • Octagon Concave Cut
  • Octagon Facet
  • Octagon Mixed-Cut
  • Octagon Step Cut
  • Oval Bar Cut
  • Oval Buff-Top
  • Oval Cabochon
  • Oval Cabochon with Hole
  • Oval Carved Cameo
  • Oval Checkerboard
  • Oval Checkerboard (double sided)
  • Oval Concave Cut
  • Oval Crystal Cluster
  • Oval Diamond-Cut
  • Oval Facet
  • Oval Fancy Facet
  • Oval Fantasy Concave Cut
  • Oval Mixed Cut
  • Oval Portuguese-Cut
  • Oval Rose-Cut
  • Oval Slice
  • Pear Cabochon
  • Pear Checkerboard
  • Pear Checkerboard with Hole
  • Pear Concave Cut
  • Pear Concave Fantasy Cut
  • Pear Crystal Cluster
  • Pear Double-Sided Checkerboard
  • Pear Facet
  • Pear Shape Sugarloaf Cabochon
  • Pear Slice
  • Pencil
  • Pencil Cut
  • Princess-Cut
  • Rhomb Cabochon
  • Rhomb Checkerboard
  • Rhomb Checkerboard (Double-Sided)
  • Rhomb Facet
  • Rondelle
  • Round Buff-Top
  • Round Cabochon
  • Round Carved Cameo
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  • Round Checkerboard (double sided)
  • Round Concave Cut
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  • Round Crystal Cluster
  • Round Drilled Checkerboard (Double Sided)
  • Round Drilled Rondelle
  • Round Facet
  • Round Mixed-Cut
  • Round Petal Cut
  • Round Portuguese-Cut
  • Round Rose-Cut
  • Round Rose-Cut (double sided)
  • Round Slice
  • Shark Fin Cabochon
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  • Square / Scissor Cut
  • Square Buff-Top
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  • Star Facet
  • Tapered Baguette Cabochon
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  • Trapezoid
  • Trapezoid Cabochon
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  • Triangle Cabochon
  • Triangle Facet
  • Trillion Cabochon
  • Trillion Checkerboard
  • Trillion Concave Cut
  • Trillion Crystal Cluster
  • Trillion Facet
  • Trillion Rose-Cut
  • Trillion Shape Sugarloaf Cabochon
  • Undrilled Briolette Teardrop
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    • S Back to Top
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Size and Weight

Gems are always measured in Millimeter (mm)

Dimensions are given as;
length x width x depth,
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