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Buy Octagon Shape 27 x 20 mm Gems

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0.40ct Natural Deep Orange Sapphire, Heart, VS, Photo A

0.40ct Natural Deep Orange Sapphire, Heart, VS

Sapphire

0.40ct1 pc
$ 29.76
4.6 x 4.5 mm
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1.63ctw Natural Sky Blue Topaz, Pear Shape, VVS, Photo A

1.63ctw Natural Sky Blue Topaz, Pear Shape, VVS

Topaz

1.63ct total2 pcs
$ 13.93
7 x 5 mm (calibrated)
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4.60ctw Natural Medium Orange Sapphire, Pear Shape, VVS-VS, Photo A

4.60ctw Natural Medium Orange Sapphire, Pear Shape, VVS-VS

Sapphire

4.60ct total20 pcs
$ 114.76
5 x 3.2 mm
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2.77ctw Natural Bluish White Rainbow Moonstone, Square, Transparent, Photo A

2.77ctw Natural Bluish White Rainbow Moonstone, Square, Transparent

Rainbow Moonstone

2.77ct total20 pcs
$ 63.25
3 x 3 mm (calibrated)
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7.19ct Natural Light Yellow Apatite, Oval, VS, Photo A
Apatite Product Video (384522)

7.19ct Natural Light Yellow Apatite, Oval, VS

Apatite

7.19ct1 pc
$ 284.72
14 x 12 mm (calibrated)
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14.77ct Natural Wine Red Ruby, Oval, Translucent, Photo A

14.77ct Natural Wine Red Ruby, Oval, Translucent

Ruby

14.77ct1 pc
$ 779.86
16 x 12 mm (calibrated)
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36.93ct Natural Blue Green Turquoise, Oval, Opaque, Photo A
Turquoise Product Video (725303)

36.93ct Natural Blue Green Turquoise, Oval, Opaque

Turquoise

36.93ct1 pc
$ 132.95
22.2 x 19.2 mm
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4.00ct Natural Multicolor White Dendritic Agate, Pear Shape, Opaque, Photo A

4.00ct Natural Multicolor White Dendritic Agate, Pear Shape, Opaque

Dendritic Agate

4.00ct1 pc
$ 3.84
14 x 10 mm (calibrated)
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0.35ct Natural Light Blue Tanzanite, Pear Shape, VVS-VS, Photo A

0.35ct Natural Light Blue Tanzanite, Pear Shape, VVS-VS

Tanzanite

0.35ct1 pc
$ 25.20
5 x 4 mm (calibrated)
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2.80ctw Natural Clear White Topaz, Cushion, VVS-VS, Photo A

2.80ctw Natural Clear White Topaz, Cushion, VVS-VS

Topaz

2.80ct total6 pcs
$ 18.48
4.5 x 4.5 mm
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11.00ctw Natural Grayish Green Seraphinite, Pear Shape, Opaque, Photo A

11.00ctw Natural Grayish Green Seraphinite, Pear Shape, Opaque

Seraphinite

11.00ct total2 pcs
$ 21.78
14 x 10 mm (calibrated)
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2.94ct Natural Multicolor Opal, Oval, Transparent, Photo A

2.94ct Natural Multicolor Opal, Oval, Transparent

Opal

2.94ct1 pc
$ 89.09
14 x 10 mm (calibrated)
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1.13ct Natural Medium Violet Spinel, Marquise, VVS, Photo A

1.13ct Natural Medium Violet Spinel, Marquise, VVS

Spinel

1.13ct1 pc
$ 126.10
10.3 x 4.8 mm
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0.62ct Natural Light Lively Green Peridot, Marquise, VS, Photo A

0.62ct Natural Light Lively Green Peridot, Marquise, VS

Peridot

0.62ct1 pc
$ 5.95
7.6 x 4 mm
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12.80ctw Natural Clear White Quartz Cat's Eye, Round, Transparent, Photo A

12.80ctw Natural Clear White Quartz Cat's Eye, Round, Transparent

Quartz Cat's Eye

12.80ct total2 pcs
$ 54.91
11 mm (calibrated)
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0.35ct Natural Orange-Gold Sapphire, Heart, VVS-VS, Photo A

0.35ct Natural Orange-Gold Sapphire, Heart, VVS-VS

Sapphire

0.35ct1 pc
$ 26.04
4.4 x 4.3 mm
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1.77ctw Natural Intense Violet Blue Tanzanite, Oval, VS, Photo A

1.77ctw Natural Intense Violet Blue Tanzanite, Oval, VS

Tanzanite

1.77ct total4 pcs
$ 148.68
5.9 x 3.8 mm
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34.14ct Natural Multicolor Jasper, Oval, Opaque, Photo A

34.14ct Natural Multicolor Jasper, Oval, Opaque

Jasper

34.14ct1 pc
$ 17.21
33.2 x 26.4 mm
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4.79ctw Natural White Zircon, Oval, VVS-VS, Photo A

4.79ctw Natural White Zircon, Oval, VVS-VS

Zircon

4.79ct total6 pcs
$ 34.66
6 x 4 mm (calibrated)
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3.48ct Natural Medium Pink Strawberry Quartz, Oval, Transparent, Photo A

3.48ct Natural Medium Pink Strawberry Quartz, Oval, Transparent

Strawberry Quartz

3.48ct1 pc
$ 31.44
11 x 9 mm (calibrated)
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1.69ct Natural Deep Orange Hessonite Garnet, Round, SI, Photo A

1.69ct Natural Deep Orange Hessonite Garnet, Round, SI

Hessonite Garnet

1.69ct1 pc
$ 37.92
7 mm (calibrated)
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43.88ct Natural Multicolor Jasper, Oval, Opaque, Photo A

43.88ct Natural Multicolor Jasper, Oval, Opaque

Jasper

43.88ct1 pc
$ 37.07
30 x 22 mm (calibrated)
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7.51ct Natural Multicolor Labradorite, Pear Shape, Translucent, Photo A

7.51ct Natural Multicolor Labradorite, Pear Shape, Translucent

Labradorite

7.51ct1 pc
$ 20.00
16 x 12 mm (calibrated)
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19.64ct Natural Medium-Light Violet Amethyst, Flower Cut, Translucent, Photo A

19.64ct Natural Medium-Light Violet Amethyst, Flower Cut, Translucent

Amethyst

19.64ct1 pc
$ 77.77
18 x 17.5 mm
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0.63ct Natural Golden Citrine, Heart, VVS-VS, Photo A

0.63ct Natural Golden Citrine, Heart, VVS-VS

Citrine

0.63ct1 pc
$ 6.05
5.9 x 5.7 mm
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1.59ctw Natural Multicolor Opal, Pear Shape, Transparent, Photo A

1.59ctw Natural Multicolor Opal, Pear Shape, Transparent

Opal

1.59ct total2 pcs
$ 47.70
9 x 6 mm (calibrated)
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1.86ct Natural Deep Orange Zircon, Oval, VVS, Photo A

1.86ct Natural Deep Orange Zircon, Oval, VVS

Zircon

1.86ct1 pc
$ 49.36
8.3 x 5.7 mm
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1.65ctw Natural Warm Green Demantoid Garnet, Oval, VS, Photo A

1.65ctw Natural Warm Green Demantoid Garnet, Oval, VS

Demantoid Garnet

1.65ct total4 pcs
$ 217.80
4.9 x 3.8 mm
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4.69ct Natural Deep Red Star Ruby, Oval, Opaque, Photo A

4.69ct Natural Deep Red Star Ruby, Oval, Opaque

Star Ruby

4.69ct1 pc
$ 90.05
9 x 7 mm (calibrated)
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1.59ctw Natural Light Sage Green Sapphire, Square, VS, Photo A

1.59ctw Natural Light Sage Green Sapphire, Square, VS

Sapphire

1.59ct total7 pcs
$ 291.98
3 x 3 mm (calibrated)
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0.53ct Natural Navy Blue Sapphire, Round, VVS, Photo A
Sapphire Product Video (467405)

0.53ct Natural Navy Blue Sapphire, Round, VVS

Sapphire

0.53ct1 pc
$ 430.16
4.8 mm
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28.30ct Natural Bluish White Rainbow Moonstone, Oval, Translucent, Photo A

28.30ct Natural Bluish White Rainbow Moonstone, Oval, Translucent

Rainbow Moonstone

28.30ct1 pc
$ 33.96
29.5 x 13.8 mm
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GemSelect Certified Store Reviews

GemSelect: Over 22 Years in the Gemstone Business! Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

This is a wonderful website

Posted By Bryan Diaz in September, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

I wish there were options for jewelry settings

Posted By Tim in May, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

I am very pleased with the ways you can filter your searches on this site, finding exactly what I want with little knowledge of what I am looking for is surprisingly easy!

Posted By Leo in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was easy to find what I wanted

Posted By Villian in December, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Its been a long time since Ive made any purchases Im satisfied with the quality.

Posted By Hard Case in December, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Ive been looking for a place to buy loose gemstones for years and was thrilled when I found this site

Posted By Bern in October, 2024
Source: Bizrate

Overall Rating -> 8 star ratings

Easy website to navigate, lots of different varieties and options to choose from.

Posted By Brian in July, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Everything was great, website user friendly, quality amazing, communication amazing, delivery amazing, everything was as expected, they done what they said they would, overall experience was amazing.

Posted By Jac in July, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

Love the ease of access. Easy to find what you are looking for, and fair pricing.

Posted By NickBehnke in October, 2024
Source: Bizrate

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 27 x 20 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.

Read All

Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

This is a wonderful website

Posted By Bryan Diaz in September, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

I wish there were options for jewelry settings

Posted By Tim in May, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

I am very pleased with the ways you can filter your searches on this site, finding exactly what I want with little knowledge of what I am looking for is surprisingly easy!

Posted By Leo in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was easy to find what I wanted

Posted By Villian in December, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Its been a long time since Ive made any purchases Im satisfied with the quality.

Posted By Hard Case in December, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Ive been looking for a place to buy loose gemstones for years and was thrilled when I found this site

Posted By Bern in October, 2024
Source: Bizrate

Overall Rating -> 8 star ratings

Easy website to navigate, lots of different varieties and options to choose from.

Posted By Brian in July, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Everything was great, website user friendly, quality amazing, communication amazing, delivery amazing, everything was as expected, they done what they said they would, overall experience was amazing.

Posted By Jac in July, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

Love the ease of access. Easy to find what you are looking for, and fair pricing.

Posted By NickBehnke in October, 2024
Source: Bizrate
Enlarged Gemstone Image