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.

Read All

Gemstone Information

Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10

Easy to use,I have spent many hours looking at the site

Posted By Skip in November, 2023

Source: Bizrate

Overall Rating -> 10

Great experience! First time buyer

Posted By Todi89 in February, 2024

Source: Bizrate

Overall Rating -> 10

I really enjoy browsing through GemSelect. The selection is always marvelous and I love how detailed everything is described. The only thing I noticed is that when browsing through my phone, the videos of the gems do not load. If there were more videos of the gems, that would be amazing, though I understand that is a lot of work on GemSelect's part! Checking out is also very fast and easy, and I love that the return policy is very good, though I hope I don't have to use it anytime soon.

Posted By ChiChi in January, 2024

Source: Bizrate

Overall Rating -> 10

Convenient selection, arrival on time

Posted By Alin in February, 2024

Source: Bizrate

Overall Rating -> 9

Good interaction with site

Posted By Brick in September, 2023

Source: Bizrate

Overall Rating -> 10

Very pleased with shopping on this site. It's easy to navigate and information about gemstones is very good.

Posted By Kate in December, 2023

Source: Bizrate

Overall Rating -> 10

it was good

Posted By Bobk in January, 2024

Source: Bizrate

Overall Rating -> 10

Purchasing from Gem Select was a pleasant and easy experience. The photos of the stones I was interested in were an accurate depiction of the stones I received. Ordering was easy and the items arrived within a week. Over all it was a very positive experience.

Posted By Dee in September, 2023

Source: Bizrate

Overall Rating -> 10

I have used Gem Select many times over the past 10 years and have always been happy with the product & services

Posted By Ordain in August, 2023

Source: Bizrate

Overall Rating -> 10

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

Posted By T-bone in October, 2023

Source: Bizrate

Overall Rating -> 8

I am currently pleased. I like the layout of the website.

Posted By RayPoppa in January, 2024

Source: Bizrate

Overall Rating -> 9

So many gorgeous stones! The only "complaint" I have is it's difficult to visualize sizes in mm. Perhaps some way to compare in inches?It has been a long time since I bought stones from Gem select, but the process wasn't too difficult.

Posted By Ktreva52 in February, 2024

Source: Bizrate

Overall Rating -> 10

I have used GemSelect for several years and plan to shop more in the further. This is a good source of information on gemstones. I love looking at and learning about them. Lot more than I ever knew existed.

Posted By Bikerwalrus in October, 2023

Source: Bizrate

Overall Rating -> 10

The website design is a bit finicky for mobile, but Im sure its most likely just a mobile issue. Amazing selection of products, great prices.

Posted By Kuba in December, 2023

Source: Bizrate

Overall Rating -> 10

I love GemSelect, photos and details are great.

Posted By #1 in February, 2024

Source: Bizrate

Gemstones A-Z

Buy Marquise Shape 20x10 mm Gems

23.87 ct Oval Howlite, 27.9 x 20.3 mm From the United States

1.58 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 20.7 x 3.1 mm

2.32 ct Loose Yellow Sapphire, 5 mm Round Cut From Tanzania

3.89 carat Orange Zircon, Diamond-Cut loose Zircon from Cambodia, Natural Untreated Gems, 7.1 mm

11.91 ct Carved Prehnite, 15.8 x 10.3 mm From South Africa

92.59 ct Drilled Sphere Rhodochrosite, 16.9 mm From South Africa

0.73 carat Round Ruby, loose Certified Ruby from Myanmar, Natural Gem, 5.5 mm

1.02 ct Purple Spinel, 7.1 x 5.1 mm Oval Cut From Tanzania

5.53 ct Diamond Cut Smoky Quartz, 11.8 mm From Brazil

0.83 ct Loose Round Cut Lapis Lazuli, 6 mm From Afghanistan

1.42 carat Swiss Blue Topaz, Oval loose Topaz from Brazil, Natural Gem, 8.1 x 6.1 mm

2.32 ct Orange Sunstone, 8.1 x 6 mm Oval Cut From India

0.83 ct Loose Pink Sapphire, 7.1 x 5.2 mm Oval Cut From Tanzania

3.34 ct Round Concave Cut Mystic Quartz, 8.1 mm From Brazil

1.83 ct Round Cut Peridot, 3.9 mm From China

0.79 ct Pink Morganite, 6.8 x 4.8 mm Oval Cut From Afghanistan

2.49 carat Oval Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gems, 6.1 x 4.1 mm

2.86 carat Trillion Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 10.1 x 10 mm

1.7 ct Pink Morganite, 8.3 x 7.9 mm Trillion Cut From Afghanistan

1.32 ct Oval Sillimanite Cat's Eye, 7.8 x 5.9 mm From Madagascar

2.79 carat Sky Blue Topaz, Oval loose Topaz from Brazil, Natural Gems, 4.9 x 3 mm

3.09 ct Blue Green Grandidierite, 9.8 x 8.8 mm Oval Cut From Madagascar

17.41 carat Pear Obsidian, loose Certified Obsidian from the United States, Natural Untreated Gem, 25.1 x 20.6 mm

0.52 ct Oval Chrysoberyl Cat's Eye, 4.5 x 4.5 mm From Sri Lanka

14.3 carat Swiss Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gem, 17 x 13.4 mm

0.59 carat Yellow Citrine, Marquise Cut loose Citrine from Brazil, Natural Untreated Gem, 8.3 x 4.3 mm

4.56 ct Oval Pietersite, 14.3 x 10.4 mm From Namibia

1.23 carat Heart Pyrope Garnet, loose Certified Pyrope Garnet from the United States, Natural Untreated Gems, 5.1 x 5.1 mm

1 carat Green Sapphire, Cushion loose Sapphire from Madagascar, Natural Gem, 6.9 x 4.8 mm

0.66 ct Marquise Cut Peridot, 8.1 x 4.1 mm From China

0.63 ct Loose Orange Sphalerite, 4.7 mm Round Cut From Spain

0.82 carat Pear Shape Peridot, loose Certified Peridot from China, Natural Untreated Gems, 5.9 x 4.1 mm

Gemstone Information

Gemstone SHOP

POLICIES

WHO ARE WE?

Gemstone EDUCATION

WE ARE LOCATED AT