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

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

Explore our stunning collection of 18 mm round gemstones, featuring a variety of 18 mm gems and 18 mm stones with exceptional carat weight. Whether you're looking for round garnets, round sapphires, round rubies, or round emeralds, our 18 mm round cuts offer unparalleled brilliance and beauty, perfect for all your fine jewelry creations. 2. Dive into the world of 18 mm round gemstones, where you'll find a range of 18 mm round stones, gems 18 mm, and expertly crafted round brilliant cuts. Our collection includes premium 18 mm round diamonds, round sapphires, round rubies, and round emeralds, all designed to deliver stunning clarity, color, and carat weight for your jewelry collection.

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

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ID: 671202
Weight: 15.26ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 32.81
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ID: 625471
Weight: 16.42ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 86.90
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ID: 598911
Weight: 16.29ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 78.05
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ID: 714392
Weight: 27.45ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 247.05
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ID: 503802
Weight: 17.43ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 69.02
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ID: 602194
Weight: 15.94ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 77.44
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ID: 406641
Weight: 24.65ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 59.16
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ID: 717165
Weight: 13.25ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 25.28
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ID: 712831
Weight: 18.67ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 156.83
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ID: 711137
Weight: 18.58ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 156.07
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ID: 711143
Weight: 19.78ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 166.15
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ID: 491705
Weight: 48.28ct (total)
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 56.72
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ID: 717023
Weight: 15.97ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 30.47
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ID: 650679
Weight: 11.67ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 32.90
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ID: 712391
Weight: 18.19ct
Size: 18 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 152.80
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ID: 712833
Weight: 19.88ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 166.99
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ID: 711630
Weight: 18.89ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 158.68
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ID: 601427
Weight: 15.46ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 75.10
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ID: 711022
Weight: 17.29ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 145.24
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ID: 669080
Weight: 17.63ct
Size: 18 mm (calibrated)
Clarity: Transparent
Content: 1 pc
Price: $ 380.81
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ID: 711140
Weight: 18.92ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 158.93
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ID: 391643
Weight: 34.12ct (total)
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 96.84
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ID: 658420
Weight: 10.45ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 37.62
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ID: 712390
Weight: 19.21ct
Size: 18 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 161.36
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ID: 391653
Weight: 29.41ct (total)
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 83.46
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ID: 602847
Weight: 14.85ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 71.94
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ID: 552037
Weight: 11.91ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 31.44
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ID: 371914
Weight: 18.40ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 109.30
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ID: 491707
Weight: 58.13ct (total)
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 68.29
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ID: 712389
Weight: 19.60ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 164.64
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ID: 712395
Weight: 18.88ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 158.59
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ID: 406635
Weight: 23.98ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 63.31
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ID: 491702
Weight: 48.88ct (total)
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 2 pcs
Price: $ 57.42
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ID: 711023
Weight: 19.39ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 162.88
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ID: 406640
Weight: 23.89ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 63.07
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ID: 711029
Weight: 19.14ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 160.78
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ID: 721363
Weight: 24.27ct
Size: 19 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 29.12
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ID: 564824
Weight: 13.11ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 51.91
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ID: 602734
Weight: 14.35ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 69.52
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ID: 427976
Weight: 15.09ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 69.72
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ID: 712836
Weight: 19.33ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 162.37
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ID: 711030
Weight: 18.76ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 157.58
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ID: 406636
Weight: 21.98ct
Size: 18 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 58.03
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ID: 427977
Weight: 15.19ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 70.18
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ID: 711146
Weight: 18.08ct
Size: 18 mm (calibrated)
Clarity: VVS
Content: 1 pc
Price: $ 151.87
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ID: 712832
Weight: 19.76ct
Size: 18 mm (calibrated)
Clarity: VVS-VS
Content: 1 pc
Price: $ 165.98
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ID: 687678
Weight: 12.37ct
Size: 18 mm (calibrated)
Clarity: Opaque
Content: 1 pc
Price: $ 36.52
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FAQs

What does "18 mm" mean when referring to gemstones?

"18 mm" indicates the diameter of a gemstone, defining the size of pieces such as 18 mm gems, 18 mm gemstones, or 18 mm round gemstones. This measurement is crucial for understanding the overall impact and carat weight of the stone.

How do 18 mm round cuts enhance a gemstone's beauty?

18 mm round cuts, especially those in a Round brilliant cut style, maximize a gemstone’s sparkle and light performance. These precise cuts are applied to 18 mm round stones, gemstone 18 mm round pieces, and gemstones 18 mm round items, ensuring exceptional brilliance.

What types of stones are available in the 18 mm category?

Our collection includes a variety of options such as 18 mm gems, 18 mm gemstones, and 18 mm round gemstones. You can find round 18 mm gemstones, round 18 mm stones, and round gemstones 18 mm, which include stunning examples like round Diamond, round Sapphire, round Ruby, and round Emerald.

How does carat weight relate to an 18 mm diameter gemstone?

The carat weight of a gemstone is closely linked to its physical size, such as an 18 mm diameter. Larger 18 mm stones and 18 mm round gemstones typically carry a higher carat weight, reflecting their size and overall value.

What role does Gemology play in our collection?

Gemology ensures that each piece, whether it’s a gemstone 18 mm round or gemstones 18 mm round, meets strict quality standards. Experts evaluate factors like the Round brilliant cut and Carat weight to certify the beauty and authenticity of 18 mm round stones, gems 18 mm, and similar pieces.

What do the terms "gems round" and "gems stones" imply in this context?

The terms gems round and gems stones refer to any gemstone that has been expertly cut into a round shape. In our collection, these terms emphasize the focus on 18 mm round designs and include items like gemstone 18 mm round, gemstones 18 mm round, and round 18 mm gemstones.

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

Gem Select has a user friendly website and the product is very good as is the price. The gems are described accurately and I always get what I think I'm getting.

Posted By Happy Customer in June, 2025
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Overall Rating -> 10 star ratings

looked at pink stones and at sapphires bought some sapphires. I love looking and collecting gemstones..

Posted By Steven M. in February, 2025
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Overall Rating -> 7 star ratings

Okay thank you.

Posted By Bepc61 in March, 2025
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Overall Rating -> 10 star ratings

very good

Posted By Son Gift in January, 2025
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Overall Rating -> 10 star ratings

Very large selection from affordable to high end I will be coming back to shop again!

Posted By GreenGator in August, 2025
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Overall Rating -> 10 star ratings

Easy to conduct search, good amount of stock to select from along with variety of prices.

Posted By Que in June, 2025
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Overall Rating -> 10 star ratings

Very good Hoping you will increase your inventory especially in the 6mm Thanks

Posted By Ibie in February, 2025
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Overall Rating -> 10 star ratings

When I need a specific stone, gem select is my go to shop. Always a good experience and a great product.

Posted By LeAnn in April, 2025
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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
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