Calibrated Size for Octagon Cut Gemstones 16x12 mm

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.

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I did not realize how small the stone was. I cannot use it for the project I wanted, but I am keeping the stone and tru to use it in something else.

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I was looking for ammolite for my husband. Other websites are not always clear about whether they have genuine ammolite or simulated ammolite. I have purchased from GemSelect before and trust that the stones are genuine. Finding the stones I want is easy, and I love all of the search filter options!

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My only complaint is that there are so many beautiful and affordable stones that I get distracted from what I planned to order.

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Gemstones A-Z

Buy Octagon Shape 16x12 mm Gems

1.27 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 14.8 x 3.1 mm

1.18 ct Yellow Beryl, 8 x 7.8 mm Trillion Cut From Madagascar

1.1 ct Blue Kyanite, 7.2 x 5.2 mm Oval Cut From Nepal

34.77 ct Loose Brown Jasper, 37.5 x 11.2 mm Pencil Cut From Indonesia

1.82 carat Orange Hessonite Garnet, Square loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 6.8 x 6.7 mm

7.21 ct Round Checkerboard Smoky Quartz, 8.1 mm From Brazil

4.11 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 12.1 x 9.9 mm

10.76 ct Orange Moonstone, 11.1 mm Round Cut From India

2.71 carat Green Sapphire, Oval loose Sapphire from Tanzania, Natural Gems, 6 x 4.9 mm

2 ct Loose Pink Tourmaline, 7.2 mm Round Cabochon From Mozambique

3.4 ct White Moonstone, 11.2 x 8.2 mm Oval Cut From India

8.01 ct Green Agate, 13.8 x 11.3 mm Oval Cut From India

31.95 ct Yellow Star Sapphire, 19.8 x 16.9 mm Oval Cut From Madagascar

1.44 carat Orange Hessonite Garnet, Emerald Cut loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 7.4 x 5.6 mm

3.94 ct Loose Oval Star Ruby, 10 x 8.8 mm From Madagascar

7.19 carat Pear Shape Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 15.9 x 11.8 mm

0.6 carat Round Ruby, loose Certified Ruby from Myanmar, Natural Gem, 4.6 mm

0.91 carat London Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gem, 7.1 x 5 mm

4.4 ct Fancy Fire Agate, 12.3 x 8.3 mm From Mexico

18.53 ct Trillion Jasper, 18.5 x 18.5 mm From Indonesia

21.84 ct Oval Cat's Eye Opal, 22.2 x 14.9 mm From Brazil

2.38 carat Sky Blue Topaz, Emerald Cut loose Topaz from Brazil, Natural Gem, 7.9 x 7.9 mm

0.64 ct Loose Orange Sapphire, 5.8 x 4.2 mm Oval Cut From Madagascar

0.82 carat Orange Hessonite Garnet, Emerald Cut loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 6.5 x 4.5 mm

12.48 ct Gray Jadeite, 17.2 x 11.8 mm Oval Cut From Myanmar

20.3 carat Bi-color Fluorite, Oval loose Fluorite from India, Natural Untreated Gem, 18.9 x 14.5 mm

0.84 carat Blue Sapphire, Cushion loose Sapphire from Madagascar, Natural Gem, 6.4 x 4.8 mm

19.27 ct Oval Pietersite, 14 x 10.1 mm From Namibia

49.54 carat Uvarovite Garnet Drusy, loose Certified Uvarovite Garnet Drusy from Russia, Natural Untreated Gem, 31.5 x 25 mm

9.9 carat Swiss Blue Topaz, Carved Fruit loose Topaz from Brazil, Natural Gem, 16.2 x 9.6 mm

0.72 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 8.8 x 3.6 mm

0.42 carat Orange Sapphire, Pear Shape loose Sapphire from Tanzania, Natural Gem, 5.9 x 3.8 mm

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