Marquise Shape 20 x 10 mm calibrated natural loose gems from 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 marquise shaped facet cut gems, gemstone carvings and cabochons available in 20 mm x 10 mm sizes. For the largest selection of colored gemstones, Shop GemSelect Online.

As a general guideline, when it comes to calibrated gems, they are not usually expected to be cut to exact measurements and specifications. But rather, they're cut with slight variance in size, though the close approximatation in size is not clearly defined, there are general guidelines for what is considered acceptable. Obviously larger and heavy carat weight stones allow more room in size for variance, while smaller stones may leave little to none. This means a large 30mm calibrated gemstone, could actually be closer to 31 millimeters. For this reason, we recommend to always view the exact size in addition to the calibrated size details. The exact size will inform you of the variance you can expect. Some setting styles are more flexible with variance, such as prong settings, while other styles of mountings may need almost an exact size to the fraction of millimeter.

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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Overall Rating -> 10

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Overall Rating -> 8

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My first order. I am anxious to see if what I ordered is what I receive.

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i love this site, the gems are always of good quality, i've been buy gifts from the site for 10 years, love it

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Overall Rating -> 10

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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Overall Rating -> 10

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Overall Rating -> 10

It was easy to navigate and I hope that the gem is as nice as the picture

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Overall Rating -> 10

Great selection of various gems, easy to navigate site

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Overall Rating -> 10

Best place to buy gem stones, dont bother shopping else where. Prices are great, no issues with shipping and customer service is the best.

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Overall Rating -> 10

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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Overall Rating -> 10

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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Selection ability was straightforward and easy.

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Overall Rating -> 10

Selection and purchasing online was very easy

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Gemstones A-Z

Buy Marquise Shape 20x10 mm Gems

28.02 ct Fancy Tiger's Eye Matrix, 31.1 x 22.3 mm From Mexico

16.79 carat Swiss Blue Topaz, Carved Fruit loose Topaz from Brazil, Natural Gem, 23.5 x 12.5 mm

15.2 carat Ammolite, loose Certified Ammolite from Canada, Natural Gem, 22.8 x 16.7 mm

3.36 ct Oval Prehnite, 9.9 x 7.7 mm From South Africa

0.99 carat Emerald Cut Opal, loose Certified Opal from Australia, Natural Untreated Gem, 9.8 x 6 mm

0.91 carat Orange Hessonite Garnet, Pear Shape loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 6.8 x 4.9 mm

2.56 carat Pink Malaya Garnet, Round loose Malaya Garnet from Tanzania, Natural Untreated Gem, 8 mm

26.79 ct Yellow Quartz, 19.1 x 19 mm Cushion Checkerboard From Brazil

3.86 carat Sky Blue Topaz, Marquise Cut loose Topaz from Brazil, Natural Gems, 11.9 x 6 mm

1.39 carat Yellow Citrine, Round loose Citrine from Brazil, Natural Untreated Gem, 7.1 mm

10.26 ct Octagon Cut Smoky Quartz, 13.5 x 13.4 mm From Brazil

3.72 carat Sky Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gems, 5.9 x 4.3 mm

5.76 ct Round Cut Prehnite, 12 mm From South Africa

3.02 ct Red Andesine Labradorite, 8.3 x 6.2 mm Oval Cut From Congo

2.57 carat Blue Tanzanite, Oval loose Tanzanite from Tanzania, Natural Gem, 9.2 x 7.3 mm

33.42 carat Pear Jasper, loose Certified Jasper from Indonesia, Natural Untreated Gem, 36.5 x 22.4 mm

9.19 ct Loose Pear Dendritic Agate, 18.4 x 13.4 mm From India

55.75 ct Fancy Jasper, 39.7 x 27.1 mm From Indonesia

1.77 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 20.6 x 3.2 mm

0.57 carat Blue Sapphire, Oval loose Sapphire from Sri Lanka, Natural Gem, 5.2 x 4.5 mm

2.5 carat Marquise Cut Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 10 x 5.1 mm

3.71 carat Half Drilled Briolette Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 11.8 mm

4 carat Square Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 4 x 3.9 mm

10.41 ct Oval Jasper, 22.2 x 16.1 mm From Indonesia

2.5 carat Round Labradorite, loose Certified Labradorite from Madagascar, Natural Untreated Gems, 6.3 mm

0.91 carat Oval Emerald, loose Certified Emerald from Colombia, Natural Gem, 6.4 x 5.5 mm

3.28 carat Swiss Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gems, 7.2 x 5.2 mm

3.2 carat Green Sapphire, Oval loose Sapphire from Tanzania, Natural Gems, 5.9 x 4.9 mm

39.75 ct Green Jadeite, 26.1 x 19.5 mm Oval Cut From Myanmar

0.93 ct Oval Cut Kornerupine, 7.5 x 5 mm From Sri Lanka

2.74 carat Pink Tourmaline, Round Cabochon loose Tourmaline from Mozambique, Natural Untreated Gems, 6.7 mm

39.43 ct Oval Idocrase, 32.3 x 24.6 mm From the United States

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