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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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15.27ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 50.19

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5.41ct Yellow Quartz, Round, Transparent

12 mm (calibrated)

$ 21.46

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8.10ct Multicolor Agate, Round, Opaque

12 mm (calibrated)

$ 13.71

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7.65ct Pink Rose Quartz, Round, Transparent

12 mm (calibrated)

$ 41.92

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6.17ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 24.47

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6.09ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 26.75

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9.33ct Multicolor Agate, Round, Opaque

12 mm (calibrated)

$ 13.16

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10.06ctw Multicolor Labradorite, Round, Translucent

12 mm (calibrated)

$ 21.65

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5.06ct Pink Rose Quartz, Round, Transparent

12 mm (calibrated)

$ 20.13

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14.02ctw Multicolor Labradorite, Round, Translucent

12 mm (calibrated)

$ 30.16

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5.29ct Yellow Quartz, Round, Transparent

12 mm (calibrated)

$ 20.98

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5.58ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 18.33

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13.84ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 45.48

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8.74ctw Multicolor Labradorite, Round, Translucent

12 mm (calibrated)

$ 19.16

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5.58ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 10.95

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5.32ct Yellow Quartz, Round, Transparent

12 mm (calibrated)

$ 17.59

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7.27ct Brown Smoky Quartz, Round, VVS-VS

12 mm (calibrated)

$ 19.91

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14.27ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 46.90

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7.27ct Black Spinel, Round, Opaque

12 mm (calibrated)

$ 23.90

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7.56ct White Quartz Cat'S Eye, Round, Transparent

12 mm (calibrated)

$ 26.93

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8.06ct Black Star Diopside, Round, Opaque

12 mm (calibrated)

$ 40.14

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5.85ct Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 9.62

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5.28ct Yellow Quartz, Round, VS

12 mm (calibrated)

$ 21.28

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10.69ctw Yellow Quartz, Round, Transparent

12 mm (calibrated)

$ 35.33

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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 always purchase my stones from GemSelect, their products are high quality and customer service is always great. I also like the fact that I am able to purchase unique items

Posted By Desperaux in November, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

Will know more once order received

Posted By Jim in September, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

If you have motion picture, then I will be more satisfied with.

Posted By Ray in November, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

This is the first time I have used this site. I was dissatisfied with the quality of gems and supplies elsewhere and decided to try GemSelect. They are awesome! I was thrilled to see the variety and the great web performance. There was the ability to search for information as well as gems. Things like the clarity rating system and caret weight of the gems. I have always loved making things and I have just started to make jewelry as a business. However I have never made a ring before and have always wanted to. On GemSelect I was able to find good quality gems to use in my creations. I am so glad the website is so easy to use. Thank you GemSelect.

Posted By PickyShopper in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

GemSelect offers excellent choices, prices & service- highly recommended! Unfortunately, prior to ordering a replacement gemstone, my jeweler neglected to mention it needed to be one that was a'cushion cuta' to fit the existing mount. Have yet to return/exchangea'

Posted By CJ in March, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

I loved it! Extensive inventory, great prices, I definitely will be buying from here again!

Posted By Lex in April, 2026
Source: Bizrate
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