Calibrated 18 x 13 mm Oval Shape Natural Loose 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 oval shapes, facet cut and cabochon gems available now in 18 x13 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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Overall Rating -> 10

Perfect size I was looking for and great price

Posted By Izzy in September, 2023

Source: Bizrate

Overall Rating -> 10

The website is well organized and works fast forward and back. Plenty of filters. Each gem is described in detail and you receive the one pictured. Gem material info and sources available. I would like to see more specifics on sources besides country- at least region or state and in the US with Turquiose which mine. Thanks!

Posted By Orchidisle in February, 2024

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

Excellent selection of products. Website easy to navigate and make purchases.

Posted By David in April, 2023

Source: Bizrate

Overall Rating -> 10

Easy to use website, made it very easy to buy. Will shop here again.

Posted By Bjorn in January, 2024

Source: Bizrate

Overall Rating -> 10

Todo muy bien en la compra ahora esperar recibir el pedido.

Posted By MAGSMX in August, 2023

Source: Bizrate

Overall Rating -> 10

I love your selection of gems. My only complaing is I wish I could put in a page number to return to that page.When there are over 60 pages of gems it is hard to return to a page with a gem I am considering.

Posted By Cahall in March, 2024

Source: Bizrate

Overall Rating -> 10

I bought a small ring green so I may practice my jewelry making.

Posted By HairyOtter in July, 2023

Source: Bizrate

Overall Rating -> 10

Always an easy experience using Gem select.

Posted By Jeff in November, 2023

Source: Bizrate

Overall Rating -> 10

I have actually done business with them before and was quite satisfied with them then.My Mother collected turtle items and when I saw the Mother of Pearl turtle...I just thought of her and decided to buy it. It's even tinier than I thought, but so adorable!The gemstones I bought are for jewelry for my daughter's birthday.

Posted By Ktreva52 in February, 2024

Source: Bizrate

Overall Rating -> 10

great. thank you

Posted By Carrotroller in July, 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

I have used this site for sseveral years now. All has been great. I started collection gems from GemSelect for years and wanted to collect at least one of most stones. I loved Safers because the mols is a 9 + and they come in every color. This is the best place to buy gems for the assortment and price. Great place to learn about gems too. Sometimes the shipping is a little on the long side. But I would give them a 9.9 out of 10 !!

Posted By Steve in July, 2023

Source: Bizrate

Overall Rating -> 10

blessed be the lord blessed be the saved blessed be the work blessed be the traveled i write down my good times in these stones and when times are gray i can still se the sunny days refract in these stones

Posted By Kickbass.2 in May, 2023

Source: Bizrate

Overall Rating -> 10

Awesome

Posted By Mic in May, 2023

Source: Bizrate

Gemstones A-Z

Buy Oval Shape 18x13 mm Gems

0.4 carat Orange Spessartite Garnet, Oval loose Spessartite Garnet from Mozambique, Natural Untreated Gem, 4.9 x 3.9 mm

17.86 ct Loose Pear Dendritic Agate, 18.3 x 13.2 mm From India

29.87 carat Bi-color Ametrine, Cushion loose Ametrine from Brazil, Natural Untreated Gem, 20.3 x 17.8 mm

3.7 carat Swiss Blue Topaz, Marquise-Cut loose Topaz from Brazil, Natural Gem, 13.8 x 8 mm

2.21 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 7 x 5.1 mm

0.72 ct Loose Pink Sapphire, 5.1 x 3.9 mm Oval Cut From Tanzania

2.36 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 7.1 x 5 mm

1.29 ct Purple Spinel, 6.6 x 6.2 mm Cushion Cut From Tanzania

1.62 carat Blue Sapphire, Diamond-Cut loose Sapphire from Madagascar, Natural Gems, 5.5 mm

1.59 carat Oval Ruby, loose Certified Ruby from Myanmar, Natural Gem, 6.9 x 6.1 mm

5.34 ct Yellow Apatite, 11.6 x 10.4 mm Octagon Cut From Madagascar

1.66 ct Round Spectrolite, 8.1 mm From Finland

0.88 ct Octagon Cut Color-Change Diaspore, 6.2 x 5 mm From Turkey

6.64 carat Black Tourmaline, Oval loose Tourmaline from Mozambique, Natural Untreated Gem, 12.8 x 10.5 mm

9.76 carat Black Tourmaline, Oval loose Tourmaline from Mozambique, Natural Untreated Gem, 14.4 x 11.4 mm

1.69 carat Orange Zircon, Oval loose Zircon from Tanzania, Natural Untreated Gem, 8 x 5.9 mm

12.8 ct Asscher Cut Rose Quartz, 14.4 x 14.2 mm From South Africa

0.21 ct White Diamond, 3 mm Diamond Cut From India

1.66 carat White Zircon, Oval loose Zircon from Cambodia, Natural Gems, 6.1 x 4.1 mm

37.78 carat Pear Jasper, loose Certified Jasper from Mexico, Natural Untreated Gem, 32.2 x 20 mm

8.64 carat Pear Pietersite, loose Certified Pietersite from Namibia, Natural Untreated Gems, 19.1 x 12.3 mm

2.36 ct Round Onyx, 5.6 mm From Sri Lanka

2.48 carat Orange Hessonite Garnet, Oval loose Hessonite Garnet from Sri Lanka, Natural Untreated Gem, 9.2 x 7.4 mm

0.75 carat Oval Emerald, loose Certified Emerald from Colombia, Natural Gem, 6.9 x 5 mm

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

8.78 ct Oval Cut Mystic Quartz, 12.1 x 10.1 mm From Brazil

1.7 ct White Moonstone, 10.5 x 8.3 mm Oval Cut From India

1.59 carat Blue Sapphire, Briolette with Hole loose Sapphire from Madagascar, Natural Gems, 4.6 mm

2.82 carat Orange Hessonite Garnet, Oval loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 9.8 x 7.6 mm

1.63 carat Heart Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 6.1 x 6.1 mm

14.83 carat Cushion Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 16 x 15.9 mm

3.13 carat Square Pyrope Garnet, loose Certified Pyrope Garnet from Madagascar, Natural Untreated Gems, 6.2 x 6.2 mm

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