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

Great site

Posted By Lord of Bananas in November, 2023

Source: Bizrate

Overall Rating -> 10

the searching format was easy to find what i needed. It helped to be able to sort Lowest price to Highest because i wasnt looking to spend too much but i did want an actual stone and not imitation.

Posted By PixelComposer in January, 2024

Source: Bizrate

Overall Rating -> 10

I was looking for a source for affordable genuine gemstones for my grandson who is currently very interested in rocks and gems. I was quite surprised and pleased to find GemSelect and finding the right stones at the right price couldn't have been simpler.

Posted By Papa in December, 2023

Source: Bizrate

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

Source: Bizrate

Overall Rating -> 9

It went well

Posted By Rob in December, 2023

Source: Bizrate

Overall Rating -> 10

The website is easy to navigate and has a great selection. I am an amateur silver smith casting jewelry with stones

Posted By Jrplunk in April, 2024

Source: Bizrate

Overall Rating -> 10

Found the stone I wanted which was delivered quickly and met expectations.

Posted By GemGrammy in January, 2024

Source: Bizrate

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

Source: Bizrate

Overall Rating -> 10

Extremely easy to use, and I am fully satisfied with the purchase process.

Posted By Fl_Beachcomber in October, 2023

Source: Bizrate

Overall Rating -> 9

Overall good, shipping prices just seem a little on the high side.

Posted By Steve in August, 2023

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

The website is very easy to use. The search function, filter and sort functions are very helpful.

Posted By Sboro in August, 2023

Source: Bizrate

Overall Rating -> 10

I purchase all of my stones from GemSelect! They're the best I've found for both selection and value.

Posted By Terry in June, 2023

Source: Bizrate

Overall Rating -> 10

Easy to use as always and in all steps from opening site to paying.

Posted By Pete in February, 2024

Source: Bizrate

Overall Rating -> 7

I placed order#384714 based on the picture on your website and the stone came in much darker. I'm sure it's the same stone i ordered but your lighting made it seem a lighter blue. I was trying to match a stone for a customer and based on the picture it would have been close enough but the stone in person is a mile off.

Posted By Bobk in February, 2024

Source: Bizrate

Gemstones A-Z

Buy Round Shape 12 mm Gems

6.94 carat Pear Shape Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 16.3 x 12.1 mm

27.1 ct Cushion Fossil Coral, 16.4 x 16.1 mm From Indonesia

9.07 ct Octagon Cut Smoky Quartz, 12.1 x 12 mm From Brazil

0.37 carat Orange Spessartite Garnet, Oval loose Spessartite Garnet from Mozambique, Natural Untreated Gem, 4.4 x 3.5 mm

6.81 carat Pear Dendritic Agate, loose Certified Dendritic Agate from India, Natural Untreated Gem, 18 x 13.4 mm

18.33 ct Fancy Jasper, 20.4 x 13.8 mm From Indonesia

0.99 carat Orange Sunstone, Oval loose Sunstone from India, Natural Untreated Gem, 8 x 6.2 mm

2.5 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 9.9 x 7.9 mm

1.23 ct Oval Sillimanite Cat's Eye, 6.8 x 4.9 mm From Madagascar

33.49 ct Blue Green Turquoise, 22.3 x 17.2 mm Oval Cut From the United States

12.08 ct Odd Shaped Druzy Variscite, 26.6 x 13.5 mm From Australia

4.52 ct Oval Rose Cut Smoky Quartz, 9.6 x 7.7 mm From Brazil

2.03 carat Brown Zircon, Oval loose Zircon from Tanzania, Natural Untreated Gem, 8.1 x 6.1 mm

4 carat Blue Zircon, Oval loose Zircon from Cambodia, Natural Gems, 5 x 3.2 mm

1.25 carat Red Tourmaline, Oval loose Tourmaline from Mozambique, Natural Untreated Gem, 7.5 x 5.7 mm

2.88 carat Square Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 4.1 x 4 mm

12.58 carat Ammolite, loose Certified Ammolite from Canada, Natural Gem, 22.6 x 12.8 mm

1.67 carat Sky Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gems, 7 x 5.1 mm

4.91 carat Oval Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gems, 9.8 x 8 mm

4.43 carat Yellow Citrine, Oval loose Citrine from Brazil, Natural Untreated Gem, 14.3 x 8.9 mm

1.71 carat Oval Opal, loose Certified Opal from Ethiopia, Natural Gems, 8.2 x 6.2 mm

51.95 ct Oval Ruby-Zoisite, 34.6 x 26.7 mm From Tanzania

13.91 ct Oval Coral, 23.3 x 17.9 mm From Indonesia

0.64 carat Blue Sapphire, Diamond-Cut loose Sapphire from Madagascar, Natural Gem, 5.2 mm

1.16 carat Oval Ruby, loose Certified Ruby from Myanmar, Natural Gem, 7.1 x 5.1 mm

3.14 carat White Topaz, Cushion loose Topaz from Brazil, Natural Untreated Gems, 4.6 x 4.6 mm

1.47 ct Yellow Beryl, 8.1 mm Round Cut From Madagascar

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

2.02 carat Oval Demantoid Garnet, loose Certified Demantoid Garnet from Namibia, Natural Untreated Gems, 4 x 3 mm

2.07 ct Yellow Sillimanite, 8 x 5.9 mm Oval Cut From Sri Lanka

5.72 ct Odd Shaped Druzy Variscite, 17.8 x 12.6 mm From China

2.4 carat Carved Leaf Ruby, loose Certified Ruby from Madagascar, Natural Gem, 14.4 x 8.4 mm

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