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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: 725002
Weight: 6.25ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 7.13
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ID: 378270
Weight: 13.85ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 54.85
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ID: 635660
Weight: 5.55ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 46.62
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ID: 600319
Weight: 6.41ct
Size: 12 mm (calibrated)
Clarity: VVS
Price: $ 30.62
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ID: 505523
Weight: 6.73ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 84.20
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ID: 516679
Weight: 5.92ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 43.52
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ID: 417762
Weight: 8.25ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Price: $ 19.61
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ID: 721524
Weight: 8.38ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 10.06
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ID: 503794
Weight: 4.20ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 16.63
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ID: 612866
Weight: 7.27ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 28.79
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ID: 470740
Weight: 7.98ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 28.73
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ID: 338284
Weight: 12.39ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 245.33
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ID: 459419
Weight: 6.34ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 12.55
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ID: 700577
Weight: 12.70ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 12.19
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ID: 470014
Weight: 13.08ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 18.12
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ID: 619135
Weight: 8.19ct (total)
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 2 pcs
Price: $ 21.62
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ID: 513225
Weight: 4.89ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 19.37
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ID: 602688
Weight: 10.79ct (total)
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 2 pcs
Price: $ 52.27
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ID: 503382
Weight: 6.21ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 40.44
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ID: 671643
Weight: 5.58ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 10.04
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ID: 464020
Weight: 5.56ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 11.00
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ID: 600322
Weight: 5.89ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Price: $ 28.14
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ID: 567110
Weight: 5.04ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 15.23
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ID: 401336
Weight: 8.77ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 28.93
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ID: 567150
Weight: 4.23ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 12.79
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ID: 500976
Weight: 6.05ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 55.91
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ID: 567738
Weight: 4.09ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 12.37
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ID: 463973
Weight: 5.52ct
Size: 12 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 10.93
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ID: 599388
Weight: 10.94ct (total)
Size: 12 mm (calibrated)
Clarity: VS
Content: 2 pcs
Price: $ 36.11
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ID: 611441
Weight: 4.72ct
Size: 12 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 16.99
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ID: 706403
Weight: 7.66ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 15.62
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ID: 684863
Weight: 7.55ct
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 10.87
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ID: 725001
Weight: 8.64ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 9.85
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ID: 567745
Weight: 5.38ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 16.26
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ID: 408052
Weight: 5.58ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 13.19
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ID: 715020
Weight: 15.47ct (total)
Size: 12 mm (calibrated)
Clarity: Translucent
Content: 2 pcs
Price: $ 40.10
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ID: 360621
Weight: 8.13ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 39.02
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ID: 625470
Weight: 6.09ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 32.23
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ID: 721522
Weight: 9.53ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 11.44
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ID: 434808
Weight: 23.25ct (total)
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 2 pcs
Price: $ 30.70
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ID: 600299
Weight: 5.17ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 24.71
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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: 548383
Weight: 13.38ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 50.16
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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: 414370
Weight: 6.88ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 45.41
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ID: 417763
Weight: 7.66ct
Size: 12 mm (calibrated)
Clarity: VVS
Price: $ 18.20
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ID: 360632
Weight: 8.40ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 44.35
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ID: 501046
Weight: 5.65ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 52.21
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ID: 612072
Weight: 13.07ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 51.76
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ID: 438436
Weight: 14.18ct (total)
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 56.15
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ID: 369730
Weight: 8.50ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 36.35
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ID: 470800
Weight: 10.97ct
Size: 12 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 506.82
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ID: 503375
Weight: 5.98ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 46.73
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ID: 699648
Weight: 4.88ct
Size: 12 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 17.57
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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: 463936
Weight: 5.08ct
Size: 12 mm (calibrated)
Clarity: VS
Price: $ 10.06
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ID: 567155
Weight: 5.96ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 18.02
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ID: 501265
Weight: 5.84ct
Size: 12 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 53.96
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ID: 619366
Weight: 5.21ct
Size: 12 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 26.34
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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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GemSelect Certified Store Reviews

GemSelect: Over 18 Years in the Gemstone Business! Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

So far, my experience was great...Thanks

Posted By Kaydi in May, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I was able to find what I was looking for

Posted By Lincolnpremier in January, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I love browsing the site and everything is easy to find. There is just so much I get lost for hours. Sometimes I wish there were videos of some gems, but other than that I love shopping with GemSelect and I have referred the site to many people many times. I work in the jewelry industry myself and I love to show off what Ive had made with my gems from GemSelect! Thank you

Posted By Antennaesglow in July, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Great for buying gemstones, came with authenticity certs. Will buy again someday!

Posted By Uggadugga in May, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Easy to conduct search, good amount of stock to select from along with variety of prices.

Posted By Que in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Loved everything. High quality, quick shipping, and authentication included.

Posted By Chris in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

All these questions, and I don't have to give any blood. What a Deal... I absolutely enjoy the Gem Select emails every month. This one today was special. I always say, I'll know it when I see it. This stone today was the One. Odd and Intriguing. Thank You So Much for all that you do.

Posted By G.W. in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Always find more niche sizes/shapes as my unconventional designs require from this website. Recommending to fellow designers in the creative atmosphere on the usual, specially due to the quality and certification of gems.

Posted By Sina in April, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I like the way your website shows us what stone were buying as well the easy way to navigate the site. also knowing the stones are real...

Posted By RED in January, 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.

Read All

Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

So far, my experience was great...Thanks

Posted By Kaydi in May, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I was able to find what I was looking for

Posted By Lincolnpremier in January, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I love browsing the site and everything is easy to find. There is just so much I get lost for hours. Sometimes I wish there were videos of some gems, but other than that I love shopping with GemSelect and I have referred the site to many people many times. I work in the jewelry industry myself and I love to show off what Ive had made with my gems from GemSelect! Thank you

Posted By Antennaesglow in July, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Great for buying gemstones, came with authenticity certs. Will buy again someday!

Posted By Uggadugga in May, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Easy to conduct search, good amount of stock to select from along with variety of prices.

Posted By Que in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Loved everything. High quality, quick shipping, and authentication included.

Posted By Chris in March, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

All these questions, and I don't have to give any blood. What a Deal... I absolutely enjoy the Gem Select emails every month. This one today was special. I always say, I'll know it when I see it. This stone today was the One. Odd and Intriguing. Thank You So Much for all that you do.

Posted By G.W. in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Always find more niche sizes/shapes as my unconventional designs require from this website. Recommending to fellow designers in the creative atmosphere on the usual, specially due to the quality and certification of gems.

Posted By Sina in April, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I like the way your website shows us what stone were buying as well the easy way to navigate the site. also knowing the stones are real...

Posted By RED in January, 2025
Source: Bizrate
Enlarged Gemstone Image