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Buy Round Shape 12 mm Gems

Round Shape 12 mm Gems Weight
Round Shape 12 mm Gems Size
Round Shape 12 mm Gems Clarity
Round Shape 12 mm Gems Price

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ID: 601512
Weight: 4.90ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 23.80
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ID: 351467
Weight: 9.88ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 43.47
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ID: 497338
Weight: 5.68ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 31.24
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ID: 566715
Weight: 5.59ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 16.90
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ID: 360617
Weight: 8.34ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 36.70
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ID: 501408
Weight: 6.39ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 49.20
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ID: 438378
Weight: 13.79ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 54.61
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ID: 608841
Weight: 11.12ct (total)
Size: 12 mm (calibrated)
Clarity: VVS
Content: 2 pcs
Price: $ 61.16
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ID: 338281
Weight: 13.62ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 224.73
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ID: 438379
Weight: 13.54ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 53.62
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ID: 601422
Weight: 5.13ct
Size: 12 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 24.92
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ID: 602738
Weight: 5.16ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 25.00
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ID: 360548
Weight: 7.56ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 39.91
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ID: 567740
Weight: 6.99ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 17.61
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ID: 438431
Weight: 15.82ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 62.65
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ID: 475302
Weight: 7.13ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 59.89
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ID: 422964
Weight: 25.67ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 27.11
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ID: 526454
Weight: avg. 12.53 ct / each
Size: 12 mm (calibrated)
Clarity: Opaque
Price: $ 15.16
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ID: 505527
Weight: 6.82ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 85.34
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ID: 608838
Weight: 10.60ct (total)
Size: 12 mm (calibrated)
Clarity: VVS
Content: 2 pcs
Price: $ 58.30
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ID: 505435
Weight: 6.50ct
Size: 12 mm (calibrated)
Clarity: Opaque
Price: $ 89.48
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ID: 625469
Weight: 5.53ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 29.28
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ID: 501048
Weight: 5.71ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 52.76
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ID: 636236
Weight: 5.46ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 45.86
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ID: 338290
Weight: 12.76ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 191.40
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ID: 566445
Weight: 24.43ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 18.38
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ID: 566966
Weight: 5.36ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 16.20
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ID: 438438
Weight: 14.30ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 56.63
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ID: 724896
Weight: 8.24ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 9.40
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ID: 497339
Weight: 5.58ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 36.83
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ID: 459719
Weight: 5.04ct
Size: 12 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 9.98
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ID: 672460
Weight: 7.02ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 19.80
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ID: 706496
Weight: 9.66ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 19.70
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ID: 505429
Weight: 5.96ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 82.06
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ID: 607799
Weight: 5.20ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 34.32
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ID: 495385
Weight: 6.50ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 42.90
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ID: 625148
Weight: 5.61ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 29.70
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ID: 338287
Weight: 13.30ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 263.34
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ID: 370166
Weight: 7.56ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 32.44
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ID: 600323
Weight: 5.82ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 27.82
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ID: 611706
Weight: 5.28ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 20.90
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ID: 548385
Weight: 11.50ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 43.12
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ID: 598886
Weight: 5.53ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 22.08
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ID: 567279
Weight: 6.73ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 20.34
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ID: 548375
Weight: 14.65ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 55.07
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ID: 505536
Weight: 6.89ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 94.82
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ID: 378277
Weight: 13.93ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 55.16
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ID: 513224
Weight: 6.67ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 26.41
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ID: 360544
Weight: 7.61ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 40.18
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ID: 548396
Weight: 14.60ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 54.73
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ID: 618964
Weight: 6.18ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 31.25
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ID: 435118
Weight: 27.60ct (total)
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 2 pcs
Price: $ 36.43
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ID: 676175
Weight: 4.12ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 11.71
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ID: 612867
Weight: 6.27ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 20.69
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ID: 503800
Weight: 5.45ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 21.59
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ID: 602442
Weight: 5.28ct
Size: 12 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 25.64
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ID: 370171
Weight: 7.51ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 32.22
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ID: 408051
Weight: 5.53ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 13.07
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ID: 548379
Weight: 12.29ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 46.07
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ID: 338262
Weight: 4.95ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 48.02
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GemSelect Certified Store Reviews

GemSelect: Over 22 Years in the Gemstone Business! Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

Good selection, using for custom jewlery for my wife.

Posted By Smitty in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I love the quality, presentation and the price of the stones. I love the identification card - report they send with each stone.

Posted By Dia in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was easy to navigate

Posted By GemGod in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Excellent selection and easy to use, well done site

Posted By Steph in December, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Good products

Posted By Brave in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I have purchased stones from gem select in the past and have been very satisfied. I expect to repeat that experience with this purchase as well

Posted By Marti in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Very fast navigation and purchase, which is good. I need to strike while the iron is hot.

Posted By Tim G. in February, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I really liked the email, and the link that help return me to the site. I didnt have access to my card info while checking out and I had to put my phone away so I lost the tab. Fortunately, since I did give an email- they sent me a link that brought me back to where I was. Greatly appreciated

Posted By Jag in January, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

I was looking for a small gift for a friend- the process is the same as every other time and was very simple, and she even got her gift early! On the downside, there's no way to easily keep track of multiple Shipping Addresses, so if I want to send a gift to Friend A and to Friend B, I have to overwrite everything and it's a fair bit clunky in that regard.

Posted By Jezzi in June, 2025
Source: Bizrate

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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Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

Good selection, using for custom jewlery for my wife.

Posted By Smitty in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I love the quality, presentation and the price of the stones. I love the identification card - report they send with each stone.

Posted By Dia in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was easy to navigate

Posted By GemGod in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Excellent selection and easy to use, well done site

Posted By Steph in December, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Good products

Posted By Brave in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I have purchased stones from gem select in the past and have been very satisfied. I expect to repeat that experience with this purchase as well

Posted By Marti in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Very fast navigation and purchase, which is good. I need to strike while the iron is hot.

Posted By Tim G. in February, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I really liked the email, and the link that help return me to the site. I didnt have access to my card info while checking out and I had to put my phone away so I lost the tab. Fortunately, since I did give an email- they sent me a link that brought me back to where I was. Greatly appreciated

Posted By Jag in January, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

I was looking for a small gift for a friend- the process is the same as every other time and was very simple, and she even got her gift early! On the downside, there's no way to easily keep track of multiple Shipping Addresses, so if I want to send a gift to Friend A and to Friend B, I have to overwrite everything and it's a fair bit clunky in that regard.

Posted By Jezzi in June, 2025
Source: Bizrate
Enlarged Gemstone Image