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Buy Octagon Shape 16x12 mm Gems

(55)
Gem Type Weight Size Clarity Price Origin
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Black Hematite Gem - 9.5ct Octagon Cabochon (ID: 515488)

Octagon / Emerald Cut Black Hematite

9.5ct
16.2 x 12.5 mm
$ 9.47
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Bi-color Ametrine Gem - 19ct Octagon / Scissor Cut (ID: 505789)

Octagon / Emerald Cut Bi-color Ametrine

19ct
16.6 x 12.5 mm
$ 95.00
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Golden Orange Citrine Gem - 12.7ct Octagon Step Cut (ID: 503629)

Octagon / Emerald Cut Golden Citrine

12.7ct
16.1 x 12 mm
$ 75.07
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Deep Golden Orange Citrine Gem - 10.7ct Octagon Facet (ID: 543821)

Octagon / Emerald Cut Golden Citrine

10.7ct
16 x 12 mm
$ 60.24
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Medium Gold Citrine Gem - 11.8ct Octagon Step Cut (ID: 503449)

Octagon / Emerald Cut Golden Citrine

11.8ct
16.1 x 12.1 mm
$ 70.09
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Gold Citrine Gem - 11.5ct Octagon Step Cut (ID: 503628)

Octagon / Emerald Cut Golden Citrine

11.5ct
16 x 12 mm
$ 67.84
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Medium-Dark Golden Citrine Gem - 12ct Octagon Step Cut (ID: 500723)

Octagon / Emerald Cut Golden Citrine

12ct
16.1 x 12 mm
$ 70.50
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Deep Golden Orange Citrine Gem - 12.1ct Octagon Step Cut (ID: 517216)

Octagon / Emerald Cut Golden Citrine

12.1ct
16.2 x 12 mm
$ 84.98
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Bright Gold Citrine Gem - 10.9ct Octagon Step Cut (ID: 500815)

Octagon / Emerald Cut Golden Citrine

10.9ct
16.1 x 12 mm
$ 63.69
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Deep Golden Orange Citrine Gem - 11.4ct Octagon Facet (ID: 543814)

Octagon / Emerald Cut Golden Citrine

11.4ct
15.8 x 11.8 mm
$ 64.07
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Dark Golden Citrine Gem - 12.8ct Octagon Facet (ID: 543826)

Octagon / Emerald Cut Golden Citrine

12.8ct
16 x 12.1 mm
$ 72.36
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Dark Golden Citrine Gem - 12.3ct Octagon Facet (ID: 543827)

Octagon / Emerald Cut Golden Citrine

12.3ct
16.2 x 12.1 mm
$ 69.32
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Deep Golden Orange Citrine Gem - 12.1ct Octagon Facet (ID: 543824)

Octagon / Emerald Cut Golden Citrine

12.1ct
15.9 x 12.1 mm
$ 68.24
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Bright Gold Citrine Gem - 12.3ct Octagon Step Cut (ID: 503451)

Octagon / Emerald Cut Golden Citrine

12.3ct
16.1 x 12.1 mm
$ 72.58
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Orange-Gold Citrine Gem - 11.9ct Octagon Facet (ID: 543812)

Octagon / Emerald Cut Golden Citrine

11.9ct
16.2 x 12 mm
$ 67.23
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Dark Golden Citrine Gem - 13.1ct Octagon Facet (ID: 543828)

Octagon / Emerald Cut Golden Citrine

13.1ct
16.2 x 12.1 mm
$ 74.05
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Deep Golden Orange Citrine Gem - 11.1ct Octagon Facet (ID: 543822)

Octagon / Emerald Cut Golden Citrine

11.1ct
16.1 x 12 mm
$ 62.38
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Golden Orange Citrine Gem - 12.9ct Octagon Step Cut (ID: 514967)

Octagon / Emerald Cut Golden Citrine

12.9ct
16.2 x 12.1 mm
$ 90.37
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Deep Golden Orange Citrine Gem - 10.5ct Octagon Step Cut (ID: 517214)

Octagon / Emerald Cut Golden Citrine

10.5ct
16 x 12 mm
$ 73.36
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Multicolor Green Bloodstone Gem - 21.6ct Octagon Cabochon (ID: 478586)

Octagon / Emerald Cut Green Bloodstone

21.6ct
16 x 12.2 mm
$ 43.12
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Deep Golden Orange Citrine Gem - 13.8ct Octagon Step Cut (ID: 517209)

Octagon / Emerald Cut Golden Citrine

13.8ct
16 x 12.1 mm
$ 96.60
Item in Stock
1 2 3
Octagon Shape 16x12 mm Gems
Some people by gems by color or price, but for many, it is best to buy gems by shape and size - especially if you're in need of a gem to replace a previous item that was lost or damaged. Calibrated Octagon shape / Emerald-Cut, faceted and cabochon gems available now in 16 x 12 mm size range. Shop a wide range of calibrated gemstones by size online at wholesale from GemSelect.

As a general guideline, when it comes to 'calibrated' gems, they are not usually expected to be cut to exact measurements. For calibrated gemstones weighing under one carat, most jewelry settings will accommodate a gem which is within 0.2 mm of the calibrated size in order to fit a standard setting. For gemstones that weigh over one carat, a larger variance is acceptable, often round shape settings will allow 0.3 mm or slightly higher even. This small variance can usually be accommodated for most standard style settings. Round-cut gemstones should also have a greater variance in acceptable size when it comes to calibration; in fact it is usually possible to mount a round stone of any size in the closest standard setting.

Certified Customer Reviews
Overall Rating -> 10 star ratings
I have purchased, many times & have always been pleased!
Posted By Jim in November, 2019
Source: Bizrate
Overall Rating -> 9 star ratings
GemSelect has a wide selection of gems with photos of the actual gem that you will be purchasing, not some stock photo. Once a purchase is made, you can print out a certificate of authenticity. You know you are getting the real thing. The pricing is competitive. Their website also has useful information about gems.The website is easy to use. I have made multiple purchases with GemSelect, and I will be back again!
Posted By GeneticBlend in November, 2019
Source: Bizrate
Overall Rating -> 10 star ratings
The shipping was fast. The gems I ordered look great and the price was good.
Posted By Jayman in November, 2019
Source: Bizrate
Overall Rating -> 10 star ratings
My experiences with Gemselect have always been quite satisfactory. The items are accurately photographed, a detailed description and provenance provided and the compare feature helps customers select the best gem for their needs. I have often recommended this source and will continue to do so.
Posted By GemGirl in November, 2019
Source: Bizrate
Overall Rating -> 10 star ratings
I ordered several specific items from Gemselect. Items are always packaged very carefully to protect the content. Gemselect always encloses a card of authenticity which documents the entire stone, its size, clarity, etc. All of the items are as they were described. I would highly recommend them to anyone who’s in the market for a gem.
Posted By Ron in November, 2019
Source: Bizrate
Overall Rating -> 9 star ratings
I frequently check the GemSelect website for a variety of gems. I've been very satisfied with the selection and quality of the top rated gems. All of the purchases I've made have turned out beautiful pieces of jewelry.
Posted By Steve in November, 2019
Source: Bizrate
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More Shapes
  • Asscher Cut
  • Baguette / Scissor Cut
  • Baguette Cabochon
  • Baguette Checkerboard
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  • Baguette Facet
  • Baguette Rose-Cut
  • Baguette Step Cut
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  • 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 Slice
  • Drop / Pear
  • Fancy Cabochon
  • Fancy Carved Cushion
  • Fancy Carved Oval
  • Fancy Carved Pear
  • Fancy Carved Round
  • Fancy Carved Trillion
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  • Fancy-Cut
  • Fantasy Carved Flower
  • Fantasy Carved Flower Cut
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  • Half Heart Cabochon
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  • Heart Facet
  • Heart Rose-Cut
  • Hexagon Cut
  • Marquise Buff-Top
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  • Marquise Facet
  • Marquise Mixed Cut
  • Marquise Slice
  • Marquise Sugarloaf Cabochon
  • Octagon / Scissor Cut
  • Octagon Cabochon
  • Octagon Checkerboard
  • Octagon Facet
  • Octagon Step 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
  • Pentagon Facet
  • Princess-Cut
  • Rhomb Cabochon
  • Rhomb Checkerboard
  • Rhomb Checkerboard (Double-Sided)
  • Rhomb Facet
  • Rondelle
  • Round Buff-Top
  • Round Cabochon
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  • Round Checkerboard
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  • Round Concave Cut
  • Round Concave Fantasy Cut
  • Round Drilled Checkerboard (Double Sided)
  • Round Drilled Rondelle
  • Round Facet
  • Round Mixed Cut
  • Round Mixed-Cut
  • Round Petal Cut
  • Round Portuguese-Cut
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  • Round Slice
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  • Square / Scissor Cut
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  • Tapered Baguette Cabochon
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  • Triangle Cabochon
  • Trillion Cabochon
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  • Trillion Concave Cut
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  • Trillion Shape Sugarloaf Cabochon
  • Undrilled Briolette Teardrop
Popular Gemstones
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All Gemstones (144)
A B C D E F G H I J K L M N O P Q R S T V Z
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Size and Weight

Gems are always measured in Millimeter (mm)

Dimensions are given as;
length x width x depth,
except for round stones which are;
diameter x depth

Select gems by size, not by weight!
Gem varieties vary in density, so carat weight is not a good indication of size

Note: 1ct = 0.2g

Size Comparison Chart