Calibrated 18 x 13 mm Octagon Shape Natural Gemstones: GemSelect

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 18 x 13 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 am of the opinion that the company gem select cares about the product beautiful gems it sells and the cost of the gem I purchased was small i was treated as if it cost a lot of money and product was described in detail and i felt good about the little stones i had ordered.

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The website is user friendly, has excellent selection. I've always found what I was looking for with Gem Select. When others don't have it they do. And most important, they have a way for you to pay without using PayPal. I cannot use PayPal they closed my account because of no cell phone.

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The gems were as described, which is kind of rare these days. I am happy with the purchase, and delevery on time.

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I searched for the item by description and millimeter and had my choice come up and then made the best selection.

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Gemstones A-Z

Buy Octagon Shape 18x13 mm Gems

0.45 ct Orange Sphalerite, 4.3 mm Round Cut From Spain

2.56 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 11.1 x 7.7 mm

0.72 carat Oval Opal, loose Certified Opal from Ethiopia, Natural Gems, 6.9 x 4.9 mm

7.87 ct Oval Tiger's Eye, 12.4 x 8.3 mm From Thailand

15.15 carat Gray Pearl, Ball loose Pearl from South Sea, Natural Gem, 12.9 mm

1.88 ct Yellow Beryl, 9.1 x 9 mm Trillion Cut From Madagascar

12.92 carat Pear Shape Smoky Quartz, loose Certified Smoky Quartz from Brazil, Natural Untreated Gems, 15.1 x 11.1 mm

0.18 ct Blue Apatite, 3.3 mm Round Cut From Madagascar

2.29 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 21.4 x 3.8 mm

1.42 carat Oval Ruby, loose Certified Ruby from Madagascar, Natural Gem, 6.9 x 5.1 mm

4.21 ct Oval Prehnite, 7.9 x 6.9 mm From South Africa

0.74 carat Yellow Citrine, Heart loose Citrine from Brazil, Natural Untreated Gem, 6.2 x 6 mm

19.68 ct Oval Tiger's Eye, 24.7 x 16.6 mm From Thailand

0.68 ct Loose Yellow Sapphire, 3.6 x 3.5 mm Princess Cut From Tanzania

0.66 ct Loose Yellow Sapphire, 5.7 x 4.1 mm Oval Cut From Tanzania

4.18 carat Sky Blue Topaz, Princess-Cut loose Topaz from Brazil, Natural Gems, 7.1 x 7 mm

0.72 ct Loose Yellow Sapphire, 5.2 x 4 mm Octagon Cut From Tanzania

1.17 carat Pear Shape Ruby, loose Certified Ruby from Myanmar, Natural Gem, 7.2 x 5 mm

3.44 carat Black Tourmaline, Oval loose Tourmaline from Tanzania, Natural Untreated Gem, 9.9 x 8.2 mm

0.97 carat Pear Shape Color-Change Diaspore, loose Certified Color-Change Diaspore from Turkey, Natural Untreated Gem, 11.1 x 4.5 mm

3.21 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gem, 8.9 x 6.7 mm

1.17 ct Oval Sillimanite Cat's Eye, 7.7 x 5.7 mm From Madagascar

1.78 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 17.1 x 3.5 mm

2.3 carat Yellow Citrine, Carved Flower loose Citrine from Brazil, Natural Untreated Gem, 8.3 x 8.2 mm

6.45 ct Marquise Slice Ruby in Fuchsite, 16 x 7.8 mm From Ethiopia

1.9 carat Blue Tanzanite, Marquise Cut loose Tanzanite from Tanzania, Natural Gems, 7.1 x 3.4 mm

10.17 ct Carved Rose Quartz, 22.1 x 14 mm From Brazil

3.29 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 11.2 x 9 mm

0.89 ct Oval Sillimanite Cat's Eye, 7.2 x 5.1 mm From Madagascar

20.66 carat Sky Blue Topaz, Oval loose Topaz from Brazil, Natural Gem, 19.2 x 13.3 mm

28.75 ct Brown Moonstone, 22.1 x 16.2 mm Oval Cut From India

3.03 ct Round Cut Strawberry Quartz, 9 mm From Russia

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