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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: 422964
Weight: 25.67ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 27.11
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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: 625469
Weight: 5.53ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 29.28
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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: 567740
Weight: 6.99ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 17.61
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ID: 505435
Weight: 6.50ct
Size: 12 mm (calibrated)
Clarity: Opaque
Price: $ 89.48
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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: 351467
Weight: 9.88ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 43.47
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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: 526454
Weight: avg. 12.53 ct / each
Size: 12 mm (calibrated)
Clarity: Opaque
Price: $ 15.16
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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: 438378
Weight: 13.79ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 54.61
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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: 601512
Weight: 4.90ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 23.80
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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: 338281
Weight: 13.62ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 224.73
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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: 501048
Weight: 5.71ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 52.76
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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: 602738
Weight: 5.16ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 25.00
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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: 360617
Weight: 8.34ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 36.70
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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: 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: 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 -> 8 star ratings

Loved the lot buy options

Posted By BDG in October, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

I love the gems!

Posted By MM in April, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Great experience shopping and finding what I was looking for, the only improvement I could think of would be allowing to filter more than one size at a time.

Posted By Tlicious04 in September, 2024
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

I found what I was looking for...had to look up millimeters to inches. It would be nice to see something, like a quarter, in the pix to show relative size. I plan on buy loose gemstones for every month in the calendar

Posted By TheP in January, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

I am very pleased with the ways you can filter your searches on this site, finding exactly what I want with little knowledge of what I am looking for is surprisingly easy!

Posted By Leo in March, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

Excellent selection of stones -including ones I had never heard of before -nice site and fairly easy to use

Posted By DrD in May, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It's mostly good, only some item's are easier to find through the search than the menu

Posted By Wayne in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Everything went well, the payment options are easily declined but, but once sorted out, everything is smooth. I have bought from GemSelect before and am consistently satisfied with them.

Posted By Gabe in August, 2024
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 -> 8 star ratings

Loved the lot buy options

Posted By BDG in October, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

I love the gems!

Posted By MM in April, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Great experience shopping and finding what I was looking for, the only improvement I could think of would be allowing to filter more than one size at a time.

Posted By Tlicious04 in September, 2024
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

I found what I was looking for...had to look up millimeters to inches. It would be nice to see something, like a quarter, in the pix to show relative size. I plan on buy loose gemstones for every month in the calendar

Posted By TheP in January, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

I am very pleased with the ways you can filter your searches on this site, finding exactly what I want with little knowledge of what I am looking for is surprisingly easy!

Posted By Leo in March, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

Excellent selection of stones -including ones I had never heard of before -nice site and fairly easy to use

Posted By DrD in May, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It's mostly good, only some item's are easier to find through the search than the menu

Posted By Wayne in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Everything went well, the payment options are easily declined but, but once sorted out, everything is smooth. I have bought from GemSelect before and am consistently satisfied with them.

Posted By Gabe in August, 2024
Source: Bizrate
Enlarged Gemstone Image