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Buy Octagon Shape 27 x 20 mm Gems

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21.83ct Natural Swiss Blue Topaz, Cushion, VVS-VS, Photo A

21.83ct Natural Swiss Blue Topaz, Cushion, VVS-VS

Topaz

21.83ct1 pc
$ 235.76
16 x 16 mm (calibrated)
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3.47ct Natural Warm Orange Sunstone, Oval, Transparent, Photo A

3.47ct Natural Warm Orange Sunstone, Oval, Transparent

Sunstone

3.47ct1 pc
$ 64.13
11 x 9 mm (calibrated)
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0.62ct Natural Golden Citrine, Pear Shape, VVS, Photo A

0.62ct Natural Golden Citrine, Pear Shape, VVS

Citrine

0.62ct1 pc
$ 3.72
7 x 5 mm (calibrated)
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0.87ct Natural Medium Purple Spinel, Cushion, VS-SI, Photo A

0.87ct Natural Medium Purple Spinel, Cushion, VS-SI

Spinel

0.87ct1 pc
$ 51.82
5.5 x 4.9 mm
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1.59ct Natural Honey Yellow Beryl, Round, VS, Photo A

1.59ct Natural Honey Yellow Beryl, Round, VS

Beryl

1.59ct1 pc
$ 45.79
8 mm (calibrated)
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4.35ct Natural Deep Orange-Gold Citrine, Round, VS, Photo A

4.35ct Natural Deep Orange-Gold Citrine, Round, VS

Citrine

4.35ct1 pc
$ 45.94
11 mm (calibrated)
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4.68ctw Natural Twilight Blue Star Sapphire, Oval, Opaque, Photo A

4.68ctw Natural Twilight Blue Star Sapphire, Oval, Opaque

Star Sapphire

4.68ct total4 pcs
$ 123.55
7.1 x 5.3 mm
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1.13ct Natural Deep Green Tourmaline, Oval, VVS, Photo A

1.13ct Natural Deep Green Tourmaline, Oval, VVS

Tourmaline

1.13ct1 pc
$ 54.24
6.5 x 5.8 mm
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47.87ct Natural Coral Pink Rose Quartz, Oval, Transparent, Photo A

47.87ct Natural Coral Pink Rose Quartz, Oval, Transparent

Rose Quartz

47.87ct1 pc
$ 85.30
26.5 x 21.8 mm
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9.15ct Natural Bi-color Ametrine, Octagon / Emerald Cut, VVS-VS, Photo A

9.15ct Natural Bi-color Ametrine, Octagon / Emerald Cut, VVS-VS

Ametrine

9.15ct1 pc
$ 158.17
13.4 x 11.7 mm
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0.50ct Natural Pink Sapphire, Oval, VVS-VS, Photo A

0.50ct Natural Pink Sapphire, Oval, VVS-VS

Sapphire

0.50ct1 pc
$ 56.82
6 x 4 mm (calibrated)
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3.88ct Natural Medium-Dark Golden Citrine, Oval, VVS-VS, Photo A

3.88ct Natural Medium-Dark Golden Citrine, Oval, VVS-VS

Citrine

3.88ct1 pc
$ 35.86
12.2 x 8.9 mm
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1.03ct Natural Lemon Yellow Chrysoberyl, Pear Shape, VVS, Photo A

1.03ct Natural Lemon Yellow Chrysoberyl, Pear Shape, VVS

Chrysoberyl

1.03ct1 pc
$ 144.62
8.4 x 5.2 mm
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29.12ctw Natural Clear White Quartz, Pear Shape, Transparent, Photo A

29.12ctw Natural Clear White Quartz, Pear Shape, Transparent

Quartz

29.12ct total2 pcs
$ 115.32
41.3 x 12.8 mm
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0.67ct Natural Light Blue Sapphire, Oval, VVS-VS, Photo A

0.67ct Natural Light Blue Sapphire, Oval, VVS-VS

Sapphire

0.67ct1 pc
$ 88.44
5.8 x 4.9 mm
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5.29ct Natural Light Yellow Quartz, Round, VVS, Photo A

5.29ct Natural Light Yellow Quartz, Round, VVS

Quartz

5.29ct1 pc
$ 25.62
12 mm (calibrated)
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3.44ctw Natural Merlot Red Pyrope Garnet, Pear Shape, VS, Photo A

3.44ctw Natural Merlot Red Pyrope Garnet, Pear Shape, VS

Pyrope Garnet

3.44ct total4 pcs
$ 31.79
7 x 5 mm (calibrated)
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1.55ctw Natural Dark Red Pyrope Garnet, Heart, VVS-VS, Photo A

1.55ctw Natural Dark Red Pyrope Garnet, Heart, VVS-VS

Pyrope Garnet

1.55ct total2 pcs
$ 14.33
6 x 6 mm (calibrated)
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22.23ct Natural Pinkish Violet Amethyst, Octagon / Emerald Cut, VVS, Photo A

22.23ct Natural Pinkish Violet Amethyst, Octagon / Emerald Cut, VVS

Amethyst

22.23ct1 pc
$ 213.41
20 x 15 mm (calibrated)
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16.66ct Natural Medium Dark-Purple Ruby-Zoisite, Flower Cut, Opaque, Photo A

16.66ct Natural Medium Dark-Purple Ruby-Zoisite, Flower Cut, Opaque

Ruby-Zoisite

16.66ct1 pc
$ 24.40
15.2 x 14 mm
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6.15ct Natural Deep Yellow Agate, Oval, Translucent, Photo A

6.15ct Natural Deep Yellow Agate, Oval, Translucent

Agate

6.15ct1 pc
$ 12.18
12.8 x 11.4 mm
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2.89ct Natural Deep Red Zircon, Oval, VVS, Photo A
Zircon Product Video (310983)

2.89ct Natural Deep Red Zircon, Oval, VVS

Zircon

2.89ct1 pc
$ 167.86
9 x 7 mm (calibrated)
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3.45ct Natural Dark Red Rubellite Tourmaline, Oval, VS-SI, Photo A
Rubellite Tourmaline Product Video (578039)

3.45ct Natural Dark Red Rubellite Tourmaline, Oval, VS-SI

Rubellite Tourmaline

3.45ct1 pc
$ 1,725.00
11.3 x 8.1 mm
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3.41ctw Natural White Zircon, Round, VVS-VS, Photo A

3.41ctw Natural White Zircon, Round, VVS-VS

Zircon

3.41ct total4 pcs
$ 67.52
5.5 mm (calibrated)
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3.64ctw Natural Amber Orange Sapphire, Square, VVS-VS, Photo A

3.64ctw Natural Amber Orange Sapphire, Square, VVS-VS

Sapphire

3.64ct total27 pcs
$ 110.51
2.8 x 2.7 mm
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5.23ct Natural Watermelon Tourmaline, Flower Cut, Transparent, Photo A

5.23ct Natural Watermelon Tourmaline, Flower Cut, Transparent

Tourmaline

5.23ct1 pc
$ 122.82
12 x 12 mm (calibrated)
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1.24ct Natural Earth Green Tourmaline, Oval, Transparent, Photo A

1.24ct Natural Earth Green Tourmaline, Oval, Transparent

Tourmaline

1.24ct1 pc
$ 25.61
7.4 x 5.6 mm
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1.38ct Natural Deep Orange Hessonite Garnet, Oval, VS, Photo A

1.38ct Natural Deep Orange Hessonite Garnet, Oval, VS

Hessonite Garnet

1.38ct1 pc
$ 33.12
8.1 x 6.5 mm
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16.48ct Natural Light Pink Rose Quartz, Oval, Transparent, Photo A

16.48ct Natural Light Pink Rose Quartz, Oval, Transparent

Rose Quartz

16.48ct1 pc
$ 29.38
18.1 x 12.5 mm
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0.76ct Natural Light Yellow Color-Change Diaspore, Cushion, VVS-VS, Photo A

0.76ct Natural Light Yellow Color-Change Diaspore, Cushion, VVS-VS

Color-Change Diaspore

0.76ct1 pc
$ 48.34
5.4 x 5 mm
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4.19ctw Natural Medium Gold Citrine, Pear Shape, VVS-VS, Photo A

4.19ctw Natural Medium Gold Citrine, Pear Shape, VVS-VS

Citrine

4.19ct total5 pcs
$ 29.04
8 x 5 mm (calibrated)
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0.92ct Natural Clear White Sillimanite Cat's Eye, Oval, Transparent, Photo A

0.92ct Natural Clear White Sillimanite Cat's Eye, Oval, Transparent

Sillimanite Cat's Eye

0.92ct1 pc
$ 3.46
7 x 4.8 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

I love gemstones. My father was a jeweler & I used to shop for stones for him.

Posted By Andie in September, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Loved everything. High quality, quick shipping, and authentication included.

Posted By Chris in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I've made several purchases through GemSelect in the past, although not within the last six months. Their gems are always beautiful and I have never had an issue with their prices or their stones. Even when I'm not buying, I love scrolling through their website, which is very user friendly. I especially appreciate being able to change the listing order to your own liking, such as most to least expensive, largest to smallest, etc. As with most online orders, however, I think the shipping charges are not commensurate with the actual weight of the items shipped.

Posted By DrLHS in November, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Good products

Posted By Brave in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I like the way your website shows us what stone were buying as well the easy way to navigate the site. also knowing the stones are real...

Posted By RED in January, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

love the site, the experience and the products.

Posted By Ckingpots in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Easy and convenient

Posted By Butch in September, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Good. I ts very user friendly.

Posted By Shalini in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I have ordered from Genselect before and always had a great experience. My go to source!

Posted By Kycaver 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.

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Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

I love gemstones. My father was a jeweler & I used to shop for stones for him.

Posted By Andie in September, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Loved everything. High quality, quick shipping, and authentication included.

Posted By Chris in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I've made several purchases through GemSelect in the past, although not within the last six months. Their gems are always beautiful and I have never had an issue with their prices or their stones. Even when I'm not buying, I love scrolling through their website, which is very user friendly. I especially appreciate being able to change the listing order to your own liking, such as most to least expensive, largest to smallest, etc. As with most online orders, however, I think the shipping charges are not commensurate with the actual weight of the items shipped.

Posted By DrLHS in November, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Good products

Posted By Brave in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I like the way your website shows us what stone were buying as well the easy way to navigate the site. also knowing the stones are real...

Posted By RED in January, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

love the site, the experience and the products.

Posted By Ckingpots in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Easy and convenient

Posted By Butch in September, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Good. I ts very user friendly.

Posted By Shalini in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I have ordered from Genselect before and always had a great experience. My go to source!

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