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Buy Marquise Shape 18x9 mm Gems

Marquise Shape 18x9 mm Gems Weight
Marquise Shape 18x9 mm Gems Size
Marquise Shape 18x9 mm Gems Clarity
Marquise Shape 18x9 mm Gems Price

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ID: 492113
Weight: 6.39ct
Size: 17.8 x 9.1 mm
Clarity: Opaque
Content: 1 pc
Price: $ 18.47
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ID: 492123
Weight: 7.65ct
Size: 18.1 x 9.3 mm
Clarity: Opaque
Content: 1 pc
Price: $ 20.10
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ID: 711536
Weight: 6.90ct
Size: 18 x 9 mm (calibrated)
Clarity: Translucent
Content: 1 pc
Price: $ 18.38
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ID: 386699
Weight: 4.24ct
Size: 17.7 x 9.2 mm
Clarity: Translucent
Content: 1 pc
Price: $ 34.30
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ID: 358409
Weight: 6.27ct
Size: 18.1 x 9.3 mm
Clarity: VVS-VS
Content: 1 pc
Price: $ 50.57
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ID: 387216
Weight: 5.79ct
Size: 17.9 x 9 mm
Clarity: Translucent
Content: 1 pc
Price: $ 30.58
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ID: 351409
Weight: 6.44ct
Size: 17.8 x 9.3 mm
Clarity: VS
Content: 1 pc
Price: $ 59.51
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ID: 352432
Weight: 5.48ct
Size: 17.6 x 8.8 mm
Clarity: VS
Content: 1 pc
Price: $ 50.64
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ID: 351360
Weight: 6.22ct
Size: 18 x 9 mm (calibrated)
Clarity: VS
Content: 1 pc
Price: $ 57.47
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ID: 387217
Weight: 4.90ct
Size: 18.7 x 8.8 mm
Clarity: Translucent
Content: 1 pc
Price: $ 19.40
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ID: 351407
Weight: 5.35ct
Size: 17.8 x 9 mm
Clarity: VVS-VS
Content: 1 pc
Price: $ 49.44
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ID: 492460
Weight: 7.17ct
Size: 17.9 x 9.1 mm
Clarity: Opaque
Content: 1 pc
Price: $ 20.72
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ID: 358509
Weight: 6.66ct
Size: 18.2 x 9.2 mm
Clarity: VVS
Content: 1 pc
Price: $ 53.71
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ID: 352476
Weight: 5.15ct
Size: 17.6 x 9 mm
Clarity: VVS
Content: 1 pc
Price: $ 47.59
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ID: 491187
Weight: 8.00ct
Size: 18.4 x 9.3 mm
Clarity: Opaque
Content: 1 pc
Price: $ 23.54
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ID: 386583
Weight: 11.26ct (total)
Size: 17.6 x 9.1 mm
Clarity: Translucent
Content: 4 pcs
Price: $ 100.18
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ID: 351389
Weight: 5.79ct
Size: 17.8 x 8.8 mm
Clarity: VS
Content: 1 pc
Price: $ 53.50
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ID: 386506
Weight: 3.90ct
Size: 17.9 x 9.3 mm
Clarity: Translucent
Content: 1 pc
Price: $ 31.55
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ID: 491266
Weight: 7.90ct
Size: 18 x 9.1 mm
Clarity: Opaque
Content: 1 pc
Price: $ 23.26
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ID: 491250
Weight: 6.84ct
Size: 18.3 x 9.2 mm
Clarity: Opaque
Content: 1 pc
Price: $ 20.14
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ID: 491846
Weight: 14.58ct (total)
Size: 17.6 x 9.3 mm
Clarity: Opaque
Content: 2 pcs
Price: $ 13.99
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ID: 384148
Weight: 6.90ct
Size: 17.5 x 9.3 mm
Clarity: Translucent
Content: 1 pc
Price: $ 27.32
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ID: 491731
Weight: 14.15ct (total)
Size: 18.2 x 9.3 mm
Clarity: Opaque
Content: 2 pcs
Price: $ 13.58
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ID: 358674
Weight: 6.40ct
Size: 18.1 x 9.2 mm
Clarity: VVS-VS
Content: 1 pc
Price: $ 51.53
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ID: 386509
Weight: 4.54ct
Size: 18.7 x 9 mm
Clarity: Translucent
Content: 1 pc
Price: $ 40.39
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ID: 352671
Weight: 5.15ct
Size: 17.6 x 9 mm
Clarity: VS-SI
Content: 1 pc
Price: $ 47.59
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ID: 491797
Weight: 14.56ct (total)
Size: 18.3 x 9.2 mm
Clarity: Opaque
Content: 2 pcs
Price: $ 13.98
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ID: 351394
Weight: 6.53ct
Size: 18.1 x 9 mm
Clarity: VS
Content: 1 pc
Price: $ 60.34
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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
Source: Bizrate

Overall Rating -> 10 star ratings

very good

Posted By Son Gift in January, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Good shopping experience. Website is relatively easy to use. Prices are good.

Posted By Bleep in August, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

excellent deals-excellent service-fair prices

Posted By JD in April, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

Loved the lot buy options

Posted By BDG in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I found the website easy to work with. The gemstones are lovely.

Posted By Sophie-Tiger in September, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Helpselect accomplished all personal growth goals

Posted By Mike in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I was looking for a site with every type of gem I could want for setting in luxury blades and assumed I would need to look outside the US, but GemSelect made it easy to get everything I wanted without leaving the house! Wide enough selection that I do not feel the need to look elsewhere and pricing the same.

Posted By Razormane in April, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I was able to find what I was looking for

Posted By Lincolnpremier in January, 2025
Source: Bizrate

Some people by gems by color or price, but for many, it is best to buy gems by shape and size - especially if you're in need of a gem to replace a previous item that was lost or damaged. Calibrated marquise shaped facet cut gems, gemstone carvings and cabochons available in 18 mm x 9 mm sizes. For the largest selection of colored gemstones, Shop GemSelect Online.

As a general guideline, when it comes to calibrated gems, they are not usually expected to be cut to exact measurements and specifications. But rather, they're cut with slight variance in size, though the close approximatation in size is not clearly defined, there are general guidelines for what is considered acceptable. Obviously larger and heavy carat weight stones allow more room in size for variance, while smaller stones may leave little to none. This means a large 30mm calibrated gemstone, could actually be closer to 31 millimeters. For this reason, we recommend to always view the exact size in addition to the calibrated size details. The exact size will inform you of the variance you can expect. Some setting styles are more flexible with variance, such as prong settings, while other styles of mountings may need almost an exact size to the fraction of millimeter.

For calibrated gemstones weighing under one carat, most jewelry settings will accommodate a gem which is within 0.2 mm of the calibrated size in order to fit a standard setting. For gemstones that weigh over one carat, a larger variance is acceptable, often round shape settings will allow 0.3 mm or slightly higher even. This small variance can usually be accommodated for most standard style settings. Round-cut gemstones should also have a greater variance in acceptable size when it comes to calibration; in fact it is usually possible to mount a round stone of any size in the closest standard setting.

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Over 19 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
Source: Bizrate

Overall Rating -> 10 star ratings

very good

Posted By Son Gift in January, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Good shopping experience. Website is relatively easy to use. Prices are good.

Posted By Bleep in August, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

excellent deals-excellent service-fair prices

Posted By JD in April, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

Loved the lot buy options

Posted By BDG in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I found the website easy to work with. The gemstones are lovely.

Posted By Sophie-Tiger in September, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Helpselect accomplished all personal growth goals

Posted By Mike in October, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I was looking for a site with every type of gem I could want for setting in luxury blades and assumed I would need to look outside the US, but GemSelect made it easy to get everything I wanted without leaving the house! Wide enough selection that I do not feel the need to look elsewhere and pricing the same.

Posted By Razormane in April, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I was able to find what I was looking for

Posted By Lincolnpremier in January, 2025
Source: Bizrate
Enlarged Gemstone Image