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18 mm Round Gemstones: Natural Rubies, Sapphires, Garnets, Emeralds, Tourmalines, Amethysts in 18mm Round

18 mm Round Gemstones Weight
18 mm Round Gemstones Size
18 mm Round Gemstones Clarity
18 mm Round Gemstones Price

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Multicolor 18 mm Round Gemstones
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15.26ct Green Serpentine, Round, Translucent

18 mm (calibrated)

$ 27.23

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16.42ct Yellow Quartz, Round, VVS

18 mm (calibrated)

$ 72.13

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27.45ct Blue Topaz, Round, VVS-VS

18 mm (calibrated)

$ 205.05

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15.94ct Brown Smoky Quartz, Round, VVS

18 mm (calibrated)

$ 64.28

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16.29ct Green Quartz, Round, VVS

18 mm (calibrated)

$ 64.78

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17.43ct Brown Smoky Quartz, Round, VVS

18 mm (calibrated)

$ 57.29

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24.65ct Brown Moonstone, Round, Translucent

18 mm (calibrated)

$ 49.10

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14.85ct Yellow Quartz, Round, VVS

18 mm (calibrated)

$ 59.71

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18.19ct Violet Amethyst, Round, VS

18 mm (calibrated)

$ 126.82

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18.40ct Brown Moonstone, Round, Translucent

18 mm (calibrated)

$ 90.72

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19.14ct Violet Amethyst, Round, VVS

18 mm (calibrated)

$ 133.45

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18.76ct Violet Amethyst, Round, VVS

18 mm (calibrated)

$ 130.79

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15.19ct Multicolor Pietersite, Round, Opaque

18 mm (calibrated)

$ 58.25

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24.27ct Multicolor Agate, Round, Opaque

19 mm (calibrated)

$ 24.17

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11.67ct Multicolor Pietersite, Round, Opaque

18 mm (calibrated)

$ 27.31

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21.98ct Brown Moonstone, Round, Translucent

18 mm (calibrated)

$ 48.16

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19.78ct Violet Amethyst, Round, VVS

18 mm (calibrated)

$ 137.90

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15.46ct Brown Smoky Quartz, Round, VVS-VS

18 mm (calibrated)

$ 62.33

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18.58ct Violet Amethyst, Round, VVS

18 mm (calibrated)

$ 129.54

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17.29ct Violet Amethyst, Round, VVS

18 mm (calibrated)

$ 120.55

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14.35ct Yellow Quartz, Round, VVS

18 mm (calibrated)

$ 57.70

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19.39ct Violet Amethyst, Round, VVS

18 mm (calibrated)

$ 135.19

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10.45ct Multicolor Pietersite, Round, Opaque

18 mm (calibrated)

$ 31.22

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29.41ctw Multicolor Pietersite, Round, Opaque

18 mm (calibrated)

$ 69.27

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Why Buy 18 Mm Round Gemstones 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

overall great

Posted By SR in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

Have made 2 purchases so far from GemSelect and they have been amazing! Anytime I requested additional info, videos or pictures of a particular item, the response was always timely and helpful. This is a great place to buy, if you are looking for loose stones. Highly recommend!

Posted By Britnee Rose in September, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

love the site, the experience and the products.

Posted By Ckingpots in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Love how easy the site is to use. Really love that the pictures are of actual product.

Posted By LeAnn in January, 2026
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Overall Rating -> 10 star ratings

Very pleasant

Posted By Varun in June, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

good navigation and simple interface.

Posted By Dave in April, 2026
Source: Bizrate
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