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Home Calibrated Gemstones Round Shape 12 mm Gems

Buy 12 mm Round Calibrated Gemstones from GemSelect

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

Size Explained

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For Example: 6-7
For Example: 8-9
Bi-color
Black Round Shape 12 mm Gems
Blue Round Shape 12 mm Gems
Brown Round Shape 12 mm Gems
Golden
Gray Round Shape 12 mm Gems
Green Round Shape 12 mm Gems
Multicolor Round Shape 12 mm Gems
Orange Round Shape 12 mm Gems
Pink Round Shape 12 mm Gems
Purple
Red Round Shape 12 mm Gems
Turquoise Round Shape 12 mm Gems
Violet Round Shape 12 mm Gems
White Round Shape 12 mm Gems
Yellow Round Shape 12 mm Gems
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5.77ct Brown Rutile Quartz, Round, Translucent

12 mm (calibrated)

$ 14.48

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15.15ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 49.80

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6.38ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 7.62

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10.97ct Gray Star Sapphire, Round, Opaque

12 mm (calibrated)

$ 420.66

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6.84ct Brown Tiger'S Eye, Round, Opaque

12 mm (calibrated)

$ 8.86

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9.43ctw Multicolor Labradorite, Round, Translucent

12 mm (calibrated)

$ 20.67

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6.16ct Yellow Citrine, Round, VVS

12 mm (calibrated)

$ 47.24

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12.77ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 39.74

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14.18ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 46.60

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11.38ct White Rutile Quartz, Sphere / Ball, Translucent

12 mm (calibrated)

$ 13.10

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10.25ctw Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 33.70

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13.73ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 45.13

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10.73ct Red Star Garnet, Round, Opaque

12 mm (calibrated)

$ 10.57

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6.50ct Black Cat'S Eye Scapolite, Round, Translucent

12 mm (calibrated)

$ 35.61

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10.95ct Black Star Diopside, Round, Opaque

12 mm (calibrated)

$ 54.53

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6.13ct Multicolor Pietersite, Round, Opaque

12 mm (calibrated)

$ 12.37

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7.24ct Pink Morganite, Round, Translucent

12 mm (calibrated)

$ 78.53

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7.30ct Brown Tiger'S Eye, Round, Opaque

12 mm (calibrated)

$ 9.45

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14.78ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 48.57

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5.53ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 10.85

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5.91ct Yellow Citrine, Round, VVS

12 mm (calibrated)

$ 45.33

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13.01ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 40.49

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7.66ct Multicolor Agate, Round, Opaque

12 mm (calibrated)

$ 12.96

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5.29ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 21.26

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Why Buy Round Shape 12 Mm Gems from GemSelect?

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

Great! Affordable

Posted By Spinellope in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

I needed a very specific color of tourmaline and Gem Select had it. I had to get the client to agree and then ordered the stone. It arrived better than pictured and we all were very happy.

Posted By Tim W in February, 2026
Source: Bizrate

Overall Rating -> 9 star ratings

Fast snd easy to find what I was looking for

Posted By Bawb in May, 2026
Source: Bizrate

Overall Rating -> 9 star ratings

Fast and reliable service.

Posted By Zæck in December, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

On the clarity options it goes "and better" so if youre looking for si specifically and you click si and better it still shows you basically everything. It just removes the opaques. Itd be nice if it was vs only, vss only, si only, etc

Posted By Iamnotakrustykrab in December, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Love the precise descriptions and calibrations of hte loose gemstones. Would like to have seen more variety in the size gem I was looking for.

Posted By RenoRose in January, 2026
Source: Bizrate
Enlarged Gemstone Image