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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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5.78ct Yellow Citrine, Round, VVS

12 mm (calibrated)

$ 44.33

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5.44ct Brown Smoky Quartz, Round, VVS-VS

12 mm (calibrated)

$ 8.95

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12.44ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 38.70

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6.08ct Brown Rutile Quartz, Round, Transparent

12 mm (calibrated)

$ 15.25

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7.98ct White Quartz Cat'S Eye, Round, Transparent

12 mm (calibrated)

$ 28.34

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25.59ctw Multicolor Jasper, Sphere / Ball, Opaque

12 mm (calibrated)

$ 28.04

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5.22ct Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 8.57

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5.61ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 24.65

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5.18ct Brown Smoky Quartz, Round, VVS-VS

12 mm (calibrated)

$ 8.52

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6.10ct Yellow Quartz, Round, Transparent

12 mm (calibrated)

$ 24.19

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4.72ct Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 14.10

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5.04ct Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 8.28

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5.17ct Yellow Quartz, Round, Transparent

12 mm (calibrated)

$ 20.51

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6.32ct Yellow Citrine, Round, VVS

12 mm (calibrated)

$ 48.46

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5.78ct Brown Smoky Quartz, Round, Transparent

12 mm (calibrated)

$ 24.25

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5.41ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 29.64

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7.02ctw Multicolor Pietersite, Round, Opaque

12 mm (calibrated)

$ 16.43

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11.74ct Black Star Diopside, Round, Opaque

12 mm (calibrated)

$ 58.47

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7.18ct Brown Rutile Quartz, Round, Translucent

12 mm (calibrated)

$ 17.86

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13.76ct Green Maw-Sit-Sit, Round, Opaque

12 mm (calibrated)

$ 45.23

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6.88ct Pink Rose Quartz, Round, Transparent

12 mm (calibrated)

$ 37.69

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11.50ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 35.79

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10.79ctw Yellow Quartz, Round, VVS-VS

12 mm (calibrated)

$ 43.38

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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 -> 9 star ratings

I loved the selection of gemstones you have a to z

Posted By James in May, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

the selection is good as are the prices

Posted By Old man in August, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was good. There was a large selection at prices I could afford.

Posted By Zorah in February, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

Would have bought an indigo and selenite, but neither listed. But, you do offer quite a large assortment otherwise.

Posted By JD in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Always get a nice gemstone. Just like the picture. Never disappointed

Posted By Ron T in June, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

good navigation and simple interface.

Posted By Dave in April, 2026
Source: Bizrate
Enlarged Gemstone Image