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Buy Marquise Shape 18x9 mm Gems

(15)
Marquise Shape 18x9 mm Gems Weight Marquise Shape 18x9 mm Gems Size Marquise Shape 18x9 mm Gems Clarity Marquise Shape 18x9 mm Gems Price Marquise Shape 18x9 mm Gems Origin
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Marquise Shape 18x9 mm Gems Single
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3 x 3 mm 5 x 3 mm 5 x 2.5 mm 5 x 5 mm 6 x 4 mm 6 mm 6 x 6 mm 6.5 mm 7 x 5 mm 7 mm 7 x 7 mm 8 x 6 mm 8 x 8 mm 8 mm 8 x 5 mm 8.5 mm 9 mm 9 x 9 mm 9 x 7 mm 9.5 mm 10 x 10 mm 10 x 7 mm 10 x 5 mm 10 mm 10 x 8 mm 11 x 9 mm 11 mm 11 x 11 mm 12 x 6 mm 12 mm 12 x 12 mm 12 x 8 mm 12 x 10 mm 13 x 11 mm 13 mm 13 x 9 mm 14 x 9 mm 14 x 12 mm 14 x 14 mm 14 x 10 mm 15 x 15 mm 15 x 10 mm 15 mm 16 x 12 mm 16 mm 16 x 8 mm 16 x 16 mm 18 x 13 mm 18 mm 18 x 9 mm 18 x 18 mm 20 x 15 mm 20 x 10 mm 20 mm
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Photos are of Actual Products for Sale
6.13ct Loose Amethyst | 6.13 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 9.1 mm, Photo A

6.13 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 9.1 mm

Buy Natural Amethyst, Qty: 1 pc | 6.13 carat weight Amethyst

6.13ct1 Piece
$ 47.20
17.6 x 9.1 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.13 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.6 x 9.1 mm Amethyst
Amethyst Color: Purplish Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
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7.56ct Loose Amethyst | 7.56 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 9.3 mm, Photo A

7.56 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 9.3 mm

Buy Natural Amethyst, Qty: 1 pc | 7.56 carat weight Amethyst

7.56ct1 Piece
$ 58.21
18.2 x 9.3 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 7.56 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18.2 x 9.3 mm Amethyst
Amethyst Color: Deep Purplish Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
5.85ct Loose Amethyst | 5.85 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18 x 9.2 mm, Photo A

5.85 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18 x 9.2 mm

Buy Natural Amethyst, Qty: 1 pc | 5.85 carat weight Amethyst

5.85ct1 Piece
$ 45.05
18 x 9.2 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 5.85 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18 x 9.2 mm Amethyst
Amethyst Color: Purplish Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
6.22ct Loose Amethyst | 6.22 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9 mm, Photo A

6.22 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9 mm

Buy Natural Amethyst, Qty: 1 pc | 6.22 carat weight Amethyst

6.22ct1 Piece
$ 47.89
18.1 x 9 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.22 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18.1 x 9 mm Amethyst
Amethyst Color: Deep Iris Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
5.35ct Loose Amethyst | 5.35 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.8 x 9 mm, Photo A

5.35 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.8 x 9 mm

Buy Natural Amethyst, Qty: 1 pc | 5.35 carat weight Amethyst

5.35ct1 Piece
$ 41.20
17.8 x 9 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 5.35 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.8 x 9 mm Amethyst
Amethyst Color: Deep Violet Amethyst
Amethyst Clarity: VVS-VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
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6.53ct Loose Amethyst | 6.53 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9 mm, Photo A

6.53 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9 mm

Buy Natural Amethyst, Qty: 1 pc | 6.53 carat weight Amethyst

6.53ct1 Piece
$ 50.28
18.1 x 9 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.53 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18.1 x 9 mm Amethyst
Amethyst Color: Medium Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
5.15ct Loose Amethyst | 5.15 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 9 mm, Photo A

5.15 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 9 mm

Buy Natural Amethyst, Qty: 1 pc | 5.15 carat weight Amethyst

5.15ct1 Piece
$ 39.66
17.6 x 9 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 5.15 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.6 x 9 mm Amethyst
Amethyst Color: Medium Violet Amethyst
Amethyst Clarity: VS-SI Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
5.48ct Loose Amethyst | 5.48 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 8.8 mm, Photo A

5.48 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 8.8 mm

Buy Natural Amethyst, Qty: 1 pc | 5.48 carat weight Amethyst

5.48ct1 Piece
$ 42.20
17.6 x 8.8 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 5.48 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.6 x 8.8 mm Amethyst
Amethyst Color: Medium Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
6.44ct Loose Amethyst | 6.44 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.8 x 9.3 mm, Photo A

6.44 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.8 x 9.3 mm

Buy Natural Amethyst, Qty: 1 pc | 6.44 carat weight Amethyst

6.44ct1 Piece
$ 49.59
17.8 x 9.3 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.44 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.8 x 9.3 mm Amethyst
Amethyst Color: Medium Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
6.27ct Loose Amethyst | 6.27 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9.3 mm, Photo A

6.27 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9.3 mm

Buy Natural Amethyst, Qty: 1 pc | 6.27 carat weight Amethyst

6.27ct1 Piece
$ 42.14
18.1 x 9.3 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.27 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18.1 x 9.3 mm Amethyst
Amethyst Color: Medium Purplish Violet Amethyst
Amethyst Clarity: VVS-VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
6.40ct Loose Amethyst | 6.4 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9.2 mm, Photo A

6.4 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 9.2 mm

Buy Natural Amethyst, Qty: 1 pc | 6.40 carat weight Amethyst

6.40ct1 Piece
$ 42.94
18.1 x 9.2 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.40 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18.1 x 9.2 mm Amethyst
Amethyst Color: Light-Medium Violet Amethyst
Amethyst Clarity: VVS-VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
6.66ct Loose Amethyst | 6.66 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 9.2 mm, Photo A

6.66 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 9.2 mm

Buy Natural Amethyst, Qty: 1 pc | 6.66 carat weight Amethyst

6.66ct1 Piece
$ 44.76
18.2 x 9.2 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 6.66 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 18.2 x 9.2 mm Amethyst
Amethyst Color: Medium Violet Amethyst
Amethyst Clarity: VVS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
4.49ct Loose Amethyst | 4.49 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.3 x 9 mm, Photo A

4.49 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.3 x 9 mm

Buy Natural Amethyst, Qty: 1 pc | 4.49 carat weight Amethyst

4.49ct1 Piece
$ 34.57
17.3 x 9 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 4.49 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.3 x 9 mm Amethyst
Amethyst Color: Medium Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
5.15ct Loose Amethyst | 5.15 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 9 mm, Photo A

5.15 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.6 x 9 mm

Buy Natural Amethyst, Qty: 1 pc | 5.15 carat weight Amethyst

5.15ct1 Piece
$ 39.66
17.6 x 9 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 5.15 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.6 x 9 mm Amethyst
Amethyst Color: Deep Violet Amethyst
Amethyst Clarity: VVS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart
5.79ct Loose Amethyst | 5.79 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.8 x 8.8 mm, Photo A

5.79 carat Marquise Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 17.8 x 8.8 mm

Buy Natural Amethyst, Qty: 1 pc | 5.79 carat weight Amethyst

5.79ct1 Piece
$ 44.58
17.8 x 8.8 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 5.79 ct Amethyst
Amethyst Shape: Marquise Facet Amethyst
Amethyst Size: 17.8 x 8.8 mm Amethyst
Amethyst Color: Deep Purplish Violet Amethyst
Amethyst Clarity: VS Amethyst
Amethyst Origin: Brazil Amethyst
Amethyst Treatment: Untreated
Amethyst Quantity: 1
Amethyst Certificate: GemSelect
Product Description:
View Details
Add to Cart

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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Overall Rating -> 9 star ratings

over the experience was similar to other sites i have used. The only real note I have is the checkout experience was tedious and discriminatory, i wouldn't accept visa gift cards, which not only have guaranteed funds but help protect from misuse of personal information, but would not accept my visa b/c it is a prepaid card. I don't have bank account and I have been using the prepaid card for years without issue so this was disappointing to me. I feel safer using reputable gem sites rather than amazon or ebay (I have been sold fake gems with fake certs on both), but not being able to use my own valid legitimate funds and having to find a friend to buy for me b/c I use a non-bank card like 40% of the country is insulting.

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Overall Rating -> 7 star ratings

I placed order#384714 based on the picture on your website and the stone came in much darker. I'm sure it's the same stone i ordered but your lighting made it seem a lighter blue. I was trying to match a stone for a customer and based on the picture it would have been close enough but the stone in person is a mile off.

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Overall Rating -> 10 star ratings

I was looking for ammolite for my husband. Other websites are not always clear about whether they have genuine ammolite or simulated ammolite. I have purchased from GemSelect before and trust that the stones are genuine. Finding the stones I want is easy, and I love all of the search filter options!

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