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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: 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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5.42ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 17.82

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14.62ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 45.48

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9.66ctw Multicolor Labradorite, Round, Translucent

12 mm (calibrated)

$ 21.17

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8.90ct Multicolor Ruby-Zoisite, Round, Opaque

12 mm (calibrated)

$ 21.63

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27.14ctw Brown Rutile Quartz, Sphere / Ball, Transparent

12 mm (calibrated)

$ 24.78

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11.50ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 35.79

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5.57ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 22.46

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5.52ct Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 9.07

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14.92ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 49.04

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13.85ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 45.53

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5.28ct Yellow Quartz, Round, VVS-VS

12 mm (calibrated)

$ 11.57

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11.65ctw White Rutile Quartz, Round, Transparent

12 mm (calibrated)

$ 25.53

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5.51ct Brown Smoky Quartz, Round, Transparent

12 mm (calibrated)

$ 23.12

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6.73ct Brown Rutile Quartz, Round, Translucent

12 mm (calibrated)

$ 16.88

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4.90ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 19.75

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12.95ct Gray Pearl, Sphere / Ball, Opaque

12 mm (calibrated)

$ 212.83

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10.02ctw Yellow Quartz, Round, VVS-VS

12 mm (calibrated)

$ 45.74

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8.24ct Multicolor Agate, Round, Opaque

12 mm (calibrated)

$ 7.80

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4.55ct Multicolor Black Opal, Round, Opaque

12 mm (calibrated)

$ 135.95

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4.61ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 7.58

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4.65ct Multicolor Pietersite, Round, Opaque

12 mm (calibrated)

$ 10.97

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9.27ct Black Star Diopside, Round, Opaque

12 mm (calibrated)

$ 46.16

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5.78ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 11.35

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6.15ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 12.06

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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

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 -> 10 star ratings

Web site is very simple to navigate Selection is terrific

Posted By ToRa.62 in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

overall great

Posted By SR in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

Good selection prices are reasonable!

Posted By ToRa62 in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

No problems. I had a minor address issue in the past and someone got back to me very quickly and we resolved the issue satisfactorily. I appreciated the quick, concerned response. So important when buyer/seller are so far apart in distance. Thank you Gem Select. Keep up the good work!

Posted By Orphanboy in December, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

I visited several online loose stone shops trying to find rare stones. I finally found one that I've been looking for here, and very satisfied. Looking forward to receive the item in 3 weeks.

Posted By Atsu in December, 2025
Source: Bizrate
Enlarged Gemstone Image