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Buy Octagon Shape 27 x 20 mm Gems

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0.6 carat Orange Zircon for Sale, Oval loose Zircon from Colombia, Natural Untreated Gem, 5.2 x 4 mm, Photo A

0.6 carat Orange Zircon for Sale, Oval loose Zircon from Colombia, Natural Untreated Gem, 5.2 x 4 mm

Zircon

0.60ct1 pc
$ 15.00
5.2 x 4 mm
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32.12 carat Pencil Cut Rainbow Moonstone for Sale, loose Certified Rainbow Moonstone from the United States, Natural Untreated Gem, 42.1 x 10.1 mm, Photo A

32.12 carat Pencil Cut Rainbow Moonstone for Sale, loose Certified Rainbow Moonstone from the United States, Natural Untreated Gem, 42.1 x 10.1 mm

Rainbow Moonstone

32.12ct1 pc
$ 3.21
42.1 x 10.1 mm
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2.86 carat White Topaz, Cushion loose Topaz from Brazil, Natural Untreated Gems, 4.6 x 4.6 mm, Photo A

2.86 carat White Topaz, Cushion loose Topaz from Brazil, Natural Untreated Gems, 4.6 x 4.6 mm

Topaz

2.86ct total6 pcs
$ 15.73
4.6 x 4.6 mm
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0.68 carat White Topaz, Oval loose Topaz from Brazil, Natural Untreated Gem, 6.1 x 4.1 mm, Photo A

0.68 carat White Topaz, Oval loose Topaz from Brazil, Natural Untreated Gem, 6.1 x 4.1 mm

Topaz

0.68ct1 pc
$ 4.76
6 x 4 mm (calibrated)
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25.12 carat Jasper for Sale, loose Certified Jasper from Indonesia, Natural Untreated Gems, 26.1 x 15.3 mm, Photo A

25.12 carat Jasper for Sale, loose Certified Jasper from Indonesia, Natural Untreated Gems, 26.1 x 15.3 mm

Jasper

25.12ct total2 pcs
$ 14.82
26.1 x 15.3 mm
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0.82 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gems, 5.9 x 3.9 mm, Photo A

0.82 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gems, 5.9 x 3.9 mm

Citrine

0.82ct total2 pcs
$ 5.19
6 x 4 mm (calibrated)
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15.05 carat Ammolite, loose Certified Ammolite from Canada, Natural Gem, 22.5 x 16.1 mm, Photo A

15.05 carat Ammolite, loose Certified Ammolite from Canada, Natural Gem, 22.5 x 16.1 mm

Ammolite

15.05ct1 pc
$ 150.50
22.5 x 16.1 mm
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3.17 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 12.3 x 8.4 mm, Photo A

3.17 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 12.3 x 8.4 mm

Citrine

3.17ct1 pc
$ 24.41
12.3 x 8.4 mm
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1.01 ct Loose Pink Tourmaline, 6.1 mm Round Cabochon From Mozambique, Photo A

1.01 ct Loose Pink Tourmaline, 6.1 mm Round Cabochon From Mozambique

Tourmaline

1.01ct1 pc
$ 16.81
6 mm (calibrated)
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6.84 carat Brown Moonstone for Sale, Oval loose Moonstone from India, Natural Untreated Gem, 13.3 x 10.5 mm, Photo A

6.84 carat Brown Moonstone for Sale, Oval loose Moonstone from India, Natural Untreated Gem, 13.3 x 10.5 mm

Moonstone

6.84ct1 pc
$ 14.82
13.3 x 10.5 mm
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6.15 carat Pink Morganite, Pear loose Morganite from Afghanistan, Natural Untreated Gem, 15 x 11.1 mm, Photo A

6.15 carat Pink Morganite, Pear loose Morganite from Afghanistan, Natural Untreated Gem, 15 x 11.1 mm

Morganite

6.15ct1 pc
$ 67.65
15 x 11.1 mm
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10.52 carat Black Tourmaline, Pear Shape loose Tourmaline from Tanzania, Natural Untreated Gem, 17.4 x 11.5 mm, Photo A

10.52 carat Black Tourmaline, Pear Shape loose Tourmaline from Tanzania, Natural Untreated Gem, 17.4 x 11.5 mm

Tourmaline

10.52ct1 pc
$ 52.60
17.4 x 11.5 mm
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1.42 carat Green Sphene for Sale, Oval loose Sphene from Sri Lanka, Natural Untreated Gem, 6.9 x 6.1 mm, Photo A

1.42 carat Green Sphene for Sale, Oval loose Sphene from Sri Lanka, Natural Untreated Gem, 6.9 x 6.1 mm

Sphene

1.42ct1 pc
$ 7.81
6.9 x 6.1 mm
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0.43 carat Blue Sapphire for Sale, Heart loose Sapphire from Tanzania, Natural Gem, 4.6 x 4.6 mm, Photo A

0.43 carat Blue Sapphire for Sale, Heart loose Sapphire from Tanzania, Natural Gem, 4.6 x 4.6 mm

Sapphire

0.43ct1 pc
$ 34.40
4.6 x 4.6 mm
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41.38 carat Oval Star Rose Quartz for Sale, loose Certified Star Rose Quartz from South Africa, Natural Untreated Gem, 22 x 16.9 mm, Photo A

41.38 carat Oval Star Rose Quartz for Sale, loose Certified Star Rose Quartz from South Africa, Natural Untreated Gem, 22 x 16.9 mm

Star Rose Quartz

41.38ct1 pc
$ 82.76
22 x 16.9 mm
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0.6 carat Teal Sapphire, Cushion loose Sapphire from Madagascar, Natural Gem, 5.4 x 4.2 mm, Photo A

0.6 carat Teal Sapphire, Cushion loose Sapphire from Madagascar, Natural Gem, 5.4 x 4.2 mm

Sapphire

0.60ct1 pc
$ 96.00
5.4 x 4.2 mm
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0.18 carat Round Emerald, loose Certified Emerald from Colombia, Natural Gem, 3.6 mm, Photo A

0.18 carat Round Emerald, loose Certified Emerald from Colombia, Natural Gem, 3.6 mm

Emerald

0.18ct1 pc
$ 45.00
3.5 mm (calibrated)
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1.61 carat Yellow Citrine, Heart Checkerboard loose Citrine from Brazil, Natural Untreated Gem, 8 x 7.5 mm, Photo A

1.61 carat Yellow Citrine, Heart Checkerboard loose Citrine from Brazil, Natural Untreated Gem, 8 x 7.5 mm

Citrine

1.61ct1 pc
$ 11.27
8 x 7.5 mm
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2.85 ct Loose Pink Tourmaline, 8 x 6.1 mm Oval Cabochon From Mozambique, Photo A

2.85 ct Loose Pink Tourmaline, 8 x 6.1 mm Oval Cabochon From Mozambique

Tourmaline

2.85ct total2 pcs
$ 47.42
8 x 6 mm (calibrated)
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0.75 carat Yellow Sapphire for Sale, Oval loose Sapphire from Madagascar, Natural Gem, 5.9 x 5.2 mm, Photo A

0.75 carat Yellow Sapphire for Sale, Oval loose Sapphire from Madagascar, Natural Gem, 5.9 x 5.2 mm

Sapphire

0.75ct1 pc
$ 72.03
5.9 x 5.2 mm
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2.78 carat Oval Sillimanite Cat's Eye for Sale, loose Certified Sillimanite Cat's Eye from Madagascar, Natural Untreated Gems, 7.5 x 5.1 mm, Photo A

2.78 carat Oval Sillimanite Cat's Eye for Sale, loose Certified Sillimanite Cat's Eye from Madagascar, Natural Untreated Gems, 7.5 x 5.1 mm

Sillimanite Cat's Eye

2.78ct total2 pcs
$ 9.17
7.5 x 5.1 mm
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3.94 carat Yellow Sillimanite for Sale, Oval loose Sillimanite from Sri Lanka, Natural Untreated Gems, 8.1 x 6.1 mm, Photo A

3.94 carat Yellow Sillimanite for Sale, Oval loose Sillimanite from Sri Lanka, Natural Untreated Gems, 8.1 x 6.1 mm

Sillimanite

3.94ct total2 pcs
$ 97.82
8 x 6 mm (calibrated)
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0.66 carat Green Sapphire, Cushion loose Sapphire from Tanzania, Natural Gem, 4.5 x 4.5 mm, Photo A

0.66 carat Green Sapphire, Cushion loose Sapphire from Tanzania, Natural Gem, 4.5 x 4.5 mm

Sapphire

0.66ct1 pc
$ 36.00
4.5 x 4.5 mm
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4.91 carat Yellow Quartz for Sale, Round Concave Cut loose Quartz from Brazil, Natural Gem, 11.9 mm, Photo A

4.91 carat Yellow Quartz for Sale, Round Concave Cut loose Quartz from Brazil, Natural Gem, 11.9 mm

Quartz

4.91ct1 pc
$ 19.88
12 mm (calibrated)
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37.17 ct Fancy Malachite, 21.3 x 15.5 mm From Congo, Photo A

37.17 ct Fancy Malachite, 21.3 x 15.5 mm From Congo

Malachite

37.17ct1 pc
$ 37.17
21.3 x 15.5 mm
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4.23 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 6.1 x 4.2 mm, Photo A

4.23 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 6.1 x 4.2 mm

Zircon

4.23ct total6 pcs
$ 25.50
6 x 4 mm (calibrated)
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0.3 carat Round Emerald, loose Certified Emerald from Colombia, Natural Gem, 3.9 mm, Photo A

0.3 carat Round Emerald, loose Certified Emerald from Colombia, Natural Gem, 3.9 mm

Emerald

0.30ct1 pc
$ 54.00
4 mm (calibrated)
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2.66 carat Oval Demantoid Garnet, loose Certified Demantoid Garnet from Namibia, Natural Untreated Gems, 4.1 x 3.2 mm, Photo A
Demantoid Garnet Product Video (387695)

2.66 carat Oval Demantoid Garnet, loose Certified Demantoid Garnet from Namibia, Natural Untreated Gems, 4.1 x 3.2 mm

Demantoid Garnet

2.66ct total10 pcs
$ 196.86
4.1 x 3.2 mm
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11.38 carat Black Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 16 x 9.3 mm, Photo A

11.38 carat Black Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 16 x 9.3 mm

Tourmaline

11.38ct1 pc
$ 56.90
16 x 9.3 mm
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2.2 carat Orange Hessonite Garnet, Oval loose Hessonite Garnet from Sri Lanka, Natural Untreated Gem, 8.5 x 7.1 mm, Photo A

2.2 carat Orange Hessonite Garnet, Oval loose Hessonite Garnet from Sri Lanka, Natural Untreated Gem, 8.5 x 7.1 mm

Hessonite Garnet

2.20ct1 pc
$ 48.40
8.5 x 7.1 mm
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1.39 carat Pear Shape Chrysoberyl, loose Certified Chrysoberyl from Sri Lanka, Natural Untreated Gem, 8.6 x 5.9 mm, Photo A
Chrysoberyl Product Video (366486)

1.39 carat Pear Shape Chrysoberyl, loose Certified Chrysoberyl from Sri Lanka, Natural Untreated Gem, 8.6 x 5.9 mm

Chrysoberyl

1.39ct1 pc
$ 162.64
8.6 x 5.9 mm
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20.86 carat Cushion Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 20.2 x 15.3 mm, Photo A

20.86 carat Cushion Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 20.2 x 15.3 mm

Amethyst

20.86ct1 pc
$ 146.02
20 x 15 mm (calibrated)
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Photos are of Actual Products for Sale

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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