Buy 12 mm Round Calibrated Gemstones 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 Round shapes, facet cut and cabochon gems available now in 12 mm diameter 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 around 0.3 mm or slightly higher even. This small variance can usually be accommodated for 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

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

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Overall Rating -> 10

Easy to find products I want. I've ordered several times from gem select and never any problems. Will order again. Thank you.

Posted By Ray in January, 2024

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Overall Rating -> 10

Was easy to search for many gems and mineral stones.Authenticity of natural stones is important, and I feel this site offers some assurance on this.

Posted By DanM in November, 2023

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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

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Overall Rating -> 10

I have had and will always have a great time shopping at GemSelect. It's a great web site with great products and great service.

Posted By Apps in November, 2023

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Overall Rating -> 10

Very excited and impressed with all your products. Keep up the good work....more different stones to choose from. I like Cabachons.

Posted By Meow in June, 2023

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Overall Rating -> 10

Trustworthy site. I've had several good experiences with company. Products always have met my expectations. Thank you.

Posted By Ray in February, 2024

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Overall Rating -> 10

it was good

Posted By Bobk in January, 2024

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Overall Rating -> 10

Very good, very fast, everything as described.

Posted By B in October, 2023

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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

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Overall Rating -> 10

The site was easy to shop and the payment was secure. I’m looking forward to receiving my order!

Posted By JAB93 in June, 2023

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Overall Rating -> 8

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.

Posted By Mark in March, 2024

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Overall Rating -> 10

Love Gem select. great gems for the price. Can't beet them

Posted By Apps in September, 2023

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Overall Rating -> 10

The gem stone always has a great selection of beautiful stones. The calibrated stone fit my ring perfectly. Thank you gem select !

Posted By Jen in August, 2023

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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.

Posted By J in December, 2023

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Gemstones A-Z

Buy Round Shape 12 mm Gems

2.86 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 11.1 x 9.2 mm

1.51 carat Square Rhodolite Garnet, loose Certified Rhodolite Garnet from Mozambique, Natural Untreated Gems, 4.9 x 4.9 mm

10.37 carat Pear Rainbow Moonstone, loose Certified Rainbow Moonstone from the United States, Natural Untreated Gem, 18.3 x 12.2 mm

5.66 ct Ball Black Opal, 10.6 mm From Ethiopia

6.92 ct Fancy Fire Agate, 15.5 x 10.3 mm From Mexico

7.55 ct Asscher Cut Rose Quartz, 11.9 x 11.7 mm From South Africa

5.23 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 11.9 x 10 mm

0.83 carat Pink Malaya Garnet, Round loose Malaya Garnet from Tanzania, Natural Untreated Gem, 5.7 mm

8.67 carat Pear Dendritic Agate, loose Certified Dendritic Agate from India, Natural Untreated Gem, 18.1 x 13.1 mm

22.35 ct Green Aventurine, 25.6 x 13 mm Odd Shaped From Brazil

6.87 ct Oval Star Ruby, 12.4 x 9.9 mm From Madagascar

1.03 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 20.6 x 2.6 mm

1.59 carat Square Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 5 x 4.9 mm

25.97 ct Oval Rainbow Moonstone, 24.1 x 17.2 mm From the United States

10.13 ct Round Labradorite, 10.2 mm From Madagascar

1.84 carat Yellow Citrine, Round loose Citrine from Brazil, Natural Untreated Gem, 8 mm

6.66 carat Swiss Blue Topaz, Oval loose Topaz from Brazil, Natural Gems, 10 x 8.1 mm

1.57 ct Loose Pink Tourmaline, 8.4 x 6.2 mm Oval Cabochon From Mozambique

58.13 ct Round Hematite, 18.1 mm From Brazil

5.96 carat Square Opal, loose Certified Opal from Ethiopia, Natural Untreated Gems, 4.9 x 4.8 mm

1.29 carat Orange Hessonite Garnet, Cushion loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 6.1 x 5.8 mm

0.46 carat Yellow Citrine, Cushion loose Citrine from Brazil, Natural Untreated Gem, 5.1 x 5 mm

18.36 ct Loose Pear Cut Amethyst, 21.3 x 16.1 mm From Brazil

0.44 ct Oval Checkerboard Peridot, 6 x 4 mm From China

3.17 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 11 x 9.1 mm

38.74 ct Drilled Sphere Rutile Quartz, 13.9 mm From India

1.14 carat Orange Hessonite Garnet, Baguette Cut loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 6.2 x 4.3 mm

0.81 carat London Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gem, 7.2 x 5.1 mm

0.31 carat Oval Emerald, loose Certified Emerald from Colombia, Natural Gem, 5.3 x 3.4 mm

2.48 ct Cushion Cut Peridot, 9.3 x 7.2 mm From Myanmar

2.85 ct Yellow Quartz, 9.5 x 9.3 mm Carved From Brazil

3.03 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gems, 8.1 x 6.1 mm

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