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Buy Round Shape 12 mm Gems

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Gemtype Color Shape Weight Size Clarity Price Origin
You Selected (571): Round Shape 12 mm Gems Clear All
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Brown Smoky Quartz Gem - 5.2ct Round Checkerboard (double sided) (ID: 416678)

Round Brown Smoky Quartz

5.2ct
12.1 mm
$ 7.76
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1 pc
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Silver Pearl Gem - 13ct Spherical (ID: 338171)

Sphere / Ball Gray Pearl

13ct
12.1 mm
$ 129.70
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Grayish Silver Star Sapphire Gem - 11ct Round Cabochon (ID: 470800)

Round Gray Star Sapphire

11ct
11.5 mm
$ 383.95
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Red Strawberry Quartz Gem - 5.9ct Round Facet (ID: 475301)

Round Red Strawberry Quartz

5.9ct
12 mm
$ 40.95
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2 pcs
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Green Prehnite Gem - 5.8ct Round Facet (ID: 248654)

Round Green Prehnite

5.78 ct (total 11.55ctw)
12 mm
$ 51.98
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White Quartz Cat's Eye Gem - 8.5ct Round Cabochon (ID: 360619)

Round White Quartz Cat's Eye

8.5ct
12.1 mm
$ 33.92
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2 pcs
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Blue Larimar Gem - 6.4ct Round Cabochon (ID: 505534)

Round Blue Larimar

6.38 ct (total 12.76ctw)
12.2 mm
$ 80.64
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White Quartz Cat's Eye Gem - 7.8ct Round Cabochon (ID: 360634)

Round White Quartz Cat's Eye

7.8ct
11.8 mm
$ 31.08
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Green Maw-Sit-Sit Gem - 6.6ct Round Cabochon (ID: 397238)

Round Green Maw-Sit-Sit

6.6ct
11.6 mm
$ 19.86
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Silver Pearl Gem - 13.6ct Spherical (ID: 338281)

Sphere / Ball Gray Pearl

13.6ct
12.4 mm
$ 204.30
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2 pcs
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Green Jadeite Gem - 6.8ct Round Cabochon (ID: 470604)

Round Green Jadeite

6.84 ct (total 13.68ctw)
11.7 mm
$ 41.04
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Golden Pearl Gem - 13ct Spherical (ID: 335849)

Sphere / Ball Yellow Pearl

13ct
12.3 mm
$ 265.74
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Silver Pearl Gem - 13.3ct Spherical (ID: 338211)

Sphere / Ball Gray Pearl

13.3ct
12.3 mm
$ 199.50
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Swiss Blue Topaz Gem - 9.9ct Round Concave Fantasy Cut (ID: 486154)

Round Blue Topaz

9.9ct
11.9 mm
$ 88.74
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2 pcs
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Green Jadeite Gem - 7.1ct Round Cabochon (ID: 470592)

Round Green Jadeite

7.14 ct (total 14.28ctw)
11.9 mm
$ 42.84
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Silver Pearl Gem - 13ct Spherical (ID: 338212)

Sphere / Ball Gray Pearl

13ct
12.3 mm
$ 195.60
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2 pcs
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Green Jadeite Gem - 8.1ct Round Cabochon (ID: 470598)

Round Green Jadeite

8.06 ct (total 16.12ctw)
12.1 mm
$ 48.36
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White Quartz Cat's Eye Gem - 8.4ct Round Cabochon (ID: 360624)

Round White Quartz Cat's Eye

8.4ct
12.2 mm
$ 33.56
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Green Jadeite Gem - 8ct Round Cabochon (ID: 470588)

Round Green Jadeite

8.04 ct (total 16.07ctw)
12.2 mm
$ 48.21
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Black Spinel Gem - 6.3ct Round Rose-Cut (ID: 438498)

Round Black Spinel

6.32 ct (total 12.64ctw)
11.9 mm
$ 37.92
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Deep Brown Cat's Eye Scapolite Gem - 9.1ct Round Cabochon (ID: 470428)

Round Brown Cat's Eye Scapolite

9.1ct
11.8 mm
$ 45.70
Item in Stock
Round Shape 12 mm Gems
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.

Certified Customer Reviews
Overall Rating -> 9 star ratings
Easy to shop through gemselect and will look there for future purchases.
Posted By Childcapo in February, 2019
Source: Bizrate
Overall Rating -> 10 star ratings
good value
Posted By Don in February, 2019
Source: Bizrate
Overall Rating -> 10 star ratings
It was super easy to browse all the gemstones and find exactly what you wanted. The prices were great and the checkout process was smooth. Seems like a great site, will definitely come back to find more in the future.
Posted By JMWatch Guy in February, 2019
Source: Bizrate
Overall Rating -> 9 star ratings
Ive always been pleased with quality and truth of gems rating I am a gemmologist and really like the descriptions as well . i.e cut, colour and quality Sometimes Ill choose GemSelect rather than a local wholesaler because of my regard for their quality and truth
Posted By Mango in February, 2019
Source: Bizrate
Overall Rating -> 9 star ratings
I will continue to utilize gemselect in my business as a jeweler.
Posted By Julie in February, 2019
Source: Bizrate
Overall Rating -> 10 star ratings
Very good selection, easy to navigate site and very reasonable prices. I look forward to receiving the gems and if they are everything they appeared to be I will be extremely happy. Definitely likely to purchase from this site again.
Posted By Anthony in January, 2019
Source: Bizrate
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Size and Weight

Gems are always measured in Millimeter (mm)

Dimensions are given as;
length x width x depth,
except for round stones which are;
diameter x depth

Select gems by size, not by weight!
Gem varieties vary in density, so carat weight is not a good indication of size

Note: 1ct = 0.2g

Size Comparison Chart