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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

Choose Size or Size Range
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
Single
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6.82ct Blue Larimar, Round, Opaque

12 mm (calibrated)

$ 70.83

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13.62ct Gray Pearl, Sphere / Ball, Opaque

12 mm (calibrated)

$ 186.53

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15.82ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 52.00

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5.13ct Brown Smoky Quartz, Round, VS

12 mm (calibrated)

$ 20.68

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5.53ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 24.30

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10.60ctw Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 48.39

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6.99ct Brown Rutile Quartz, Round, Translucent

12 mm (calibrated)

$ 14.62

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

12 mm (calibrated)

$ 33.13

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7.13ct Pink Strawberry Quartz, Round, Translucent

12 mm (calibrated)

$ 49.71

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5.59ct Brown Rutile Quartz, Round, Transparent

12 mm (calibrated)

$ 14.03

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12.53ct Brown Tiger'S Eye, Sphere / Ball, Opaque

12 mm (calibrated)

$ 12.58

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25.67ctw Brown Tiger'S Eye, Sphere / Ball, Opaque

12 mm (calibrated)

$ 22.50

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6.50ct Blue Larimar, Round, Opaque

12 mm (calibrated)

$ 74.27

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4.90ct Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 19.75

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11.12ctw Yellow Quartz, Round, VVS

12 mm (calibrated)

$ 50.76

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13.54ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 44.50

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14.30ctw Black Spinel, Round, Opaque

12 mm (calibrated)

$ 47.00

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5.36ct Brown Rutile Quartz, Round, Transparent

12 mm (calibrated)

$ 13.45

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12.76ct Brown Pearl, Sphere / Ball, Opaque

12 mm (calibrated)

$ 158.86

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24.43ctw Brown Tiger'S Eye, Sphere / Ball, Opaque

12 mm (calibrated)

$ 15.26

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5.46ct Violet Amethyst, Round, Transparent

12 mm (calibrated)

$ 38.06

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8.19ctw Multicolor Labradorite, Round, Translucent

12 mm (calibrated)

$ 17.94

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4.89ct Brown Smoky Quartz, Round, VVS

12 mm (calibrated)

$ 16.08

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6.41ct Brown Smoky Quartz, Round, VVS-VS

12 mm (calibrated)

$ 12.57

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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

Had to get here via the Facebook page. Googling direct brought up an error message.

Posted By Chip in May, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

My experience has always been fantastic. Today I saved 6 gems to email a customer looking for a particular color blend to fit into an east west setting, so her options were limited, but we found one she wanted, deleted all the others in the cart and order the gem she selected. It was helpful to be able to put them in the cart so I could save them until she selected the one she wanted without having to research all of them again.

Posted By RJ in January, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

Easy and functional

Posted By Dessa in March, 2026
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

My experience was done with ease

Posted By Barb in October, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Enjoy every moment

Posted By Ferns in October, 2025
Source: Bizrate
Enlarged Gemstone Image