search
  • Sign In
    Sign Up

  • English speaking customer support only

    1-800-464-1640

    International:

    +66-39601289

  • Change Language
  • USD
  • CART
FREE SHIPPING

Buy Octagon Shape 18x13 mm Gems

(12)
Octagon Shape 18x13 mm Gems Weight Octagon Shape 18x13 mm Gems Size Octagon Shape 18x13 mm Gems Clarity Octagon Shape 18x13 mm Gems Price Octagon Shape 18x13 mm Gems Origin
More
Octagon Shape 18x13 mm Gems Single
Octagon Shape 18x13 mm Gems Pairs
Octagon Shape 18x13 mm Gems Lots
Octagon Shape 18x13 mm Gems Faceted
Octagon Shape 18x13 mm Gems Cabochons
Sort By:
Clear All
Photos are of Actual Products for Sale
13.52ct Loose Citrine | 13.52 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 18 x 13 mm, Photo A

13.52 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 18 x 13 mm

Natural Citrine, Qty: 1 pc | 13.52 carat weight Citrine

13.52ct1 Piece
$ 94.64
18 x 13 mm
Item Description
Stone Type: Loose Citrine
Citrine Weight: 13.52 ct Citrine
Citrine Shape: Octagon Step Cut Citrine
Citrine Size: 18 x 13 mm Citrine
Citrine Color: Medium Golden Citrine
Citrine Clarity: VS Citrine
Citrine Origin: Brazil Citrine
Citrine Treatment: Untreated
Citrine Quantity: 1
Citrine Certificate: GemSelect
Product Description:
View Details
Add to Cart
20.43ct Loose Apatite | 20.43 ct Yellow Apatite, 17.5 x 13.2 mm Octagon Cut From Madagascar, Photo A
Click for Product Video (384010)

20.43 ct Yellow Apatite, 17.5 x 13.2 mm Octagon Cut From Madagascar

Natural Apatite, Qty: 1 pc | 20.43 carat weight Apatite

20.43ct1 Piece
$ 612.90
17.5 x 13.2 mm
Item Description
Stone Type: Loose Apatite
Apatite Weight: 20.43 ct Apatite
Apatite Shape: Octagon Facet Apatite
Apatite Size: 17.5 x 13.2 mm Apatite
Apatite Color: Yellow Brown Apatite
Apatite Clarity: VS-SI Apatite
Apatite Origin: Madagascar Apatite
Apatite Treatment: Untreated
Apatite Quantity: 1
Apatite Certificate: GemSelect
Product Description:
View Details
Add to Cart
11.88ct Loose Citrine | 11.88 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 17.8 x 12.9 mm, Photo A

11.88 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 17.8 x 12.9 mm

Natural Citrine, Qty: 1 pc | 11.88 carat weight Citrine

11.88ct1 Piece
$ 83.16
17.8 x 12.9 mm
Item Description
Stone Type: Loose Citrine
Citrine Weight: 11.88 ct Citrine
Citrine Shape: Octagon Step Cut Citrine
Citrine Size: 17.8 x 12.9 mm Citrine
Citrine Color: Medium Gold Citrine
Citrine Clarity: VVS Citrine
Citrine Origin: Brazil Citrine
Citrine Treatment: Untreated
Citrine Quantity: 1
Citrine Certificate: GemSelect
Product Description:
View Details
Add to Cart
14.68ct Loose Citrine | 14.68 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 17.9 x 12.9 mm, Photo A
Click for Product Video (634969)

14.68 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 17.9 x 12.9 mm

Natural Citrine, Qty: 1 pc | 14.68 carat weight Citrine

14.68ct1 Piece
$ 102.76
17.9 x 12.9 mm
Item Description
Stone Type: Loose Citrine
Citrine Weight: 14.68 ct Citrine
Citrine Shape: Octagon Step Cut Citrine
Citrine Size: 17.9 x 12.9 mm Citrine
Citrine Color: Golden-Yellow Citrine
Citrine Clarity: VVS Citrine
Citrine Origin: Brazil Citrine
Citrine Treatment: Untreated
Citrine Quantity: 1
Citrine Certificate: GemSelect
Product Description:
View Details
Add to Cart
14.92ct Loose Amethyst | 14.92 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18 x 13.1 mm, Photo A

14.92 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18 x 13.1 mm

Natural Amethyst, Qty: 1 pc | 14.92 carat weight Amethyst

14.92ct1 Piece
$ 104.44
18 x 13.1 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 14.92 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18 x 13.1 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
15.66ct Loose Amethyst | 15.66 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.3 x 13.3 mm, Photo A

15.66 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.3 x 13.3 mm

Natural Amethyst, Qty: 1 pc | 15.66 carat weight Amethyst

15.66ct1 Piece
$ 109.62
18.3 x 13.3 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 15.66 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18.3 x 13.3 mm Amethyst
Amethyst Color: Medium 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
15.67ct Loose Amethyst | 15.67 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.3 x 13.2 mm, Photo A

15.67 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.3 x 13.2 mm

Natural Amethyst, Qty: 1 pc | 15.67 carat weight Amethyst

15.67ct1 Piece
$ 109.69
18.3 x 13.2 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 15.67 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18.3 x 13.2 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
14.44ct Loose Amethyst | 14.44 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.5 x 13.3 mm, Photo A

14.44 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.5 x 13.3 mm

Natural Amethyst, Qty: 1 pc | 14.44 carat weight Amethyst

14.44ct1 Piece
$ 101.08
18.5 x 13.3 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 14.44 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18.5 x 13.3 mm Amethyst
Amethyst Color: Deep 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
12.21ct Loose Amethyst | 12.21 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 13.1 mm, Photo A

12.21 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.1 x 13.1 mm

Natural Amethyst, Qty: 1 pc | 12.21 carat weight Amethyst

12.21ct1 Piece
$ 85.47
18.1 x 13.1 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 12.21 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18.1 x 13.1 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
15.55ct Loose Amethyst | 15.55 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 13.1 mm, Photo A

15.55 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 13.1 mm

Natural Amethyst, Qty: 1 pc | 15.55 carat weight Amethyst

15.55ct1 Piece
$ 108.85
18.2 x 13.1 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 15.55 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18.2 x 13.1 mm Amethyst
Amethyst Color: 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
21.73ct Loose Kunzite | 21.73 ct Loose Pink Kunzite, 18.2 x 13.4 mm Octagon Cut From Afghanistan, Photo A

21.73 ct Loose Pink Kunzite, 18.2 x 13.4 mm Octagon Cut From Afghanistan

Natural Kunzite, Qty: 1 pc | 21.73 carat weight Kunzite

21.73ct1 Piece
$ 575.85
18.2 x 13.4 mm
Item Description
Stone Type: Loose Kunzite
Kunzite Weight: 21.73 ct Kunzite
Kunzite Shape: Octagon Step Cut Kunzite
Kunzite Size: 18.2 x 13.4 mm Kunzite
Kunzite Color: Very Light Pink Kunzite
Kunzite Clarity: VVS-VS Kunzite
Kunzite Origin: Afghanistan Kunzite
Kunzite Treatment: Untreated
Kunzite Quantity: 1
Kunzite Certificate: GemSelect
Product Description:
View Details
Add to Cart
15.58ct Loose Amethyst | 15.58 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 13.4 mm, Photo A

15.58 carat Emerald Cut Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 18.2 x 13.4 mm

Natural Amethyst, Qty: 1 pc | 15.58 carat weight Amethyst

15.58ct1 Piece
$ 109.06
18.2 x 13.4 mm
Item Description
Stone Type: Loose Amethyst
Amethyst Weight: 15.58 ct Amethyst
Amethyst Shape: Octagon Step Cut Amethyst
Amethyst Size: 18.2 x 13.4 mm Amethyst
Amethyst Color: Medium 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 Octagon shape / Emerald-Cut, faceted and cabochon gems available now in 18 x 13 mm size range. Shop a wide range of calibrated gemstones by size online at wholesale from GemSelect.

As a general guideline, when it comes to 'calibrated' gems, they are not usually expected to be cut to exact measurements. 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.

Read All

Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

It was easy to find the color gem I desired and checkout was simple as well. Very excited to receive my gemstone.

Posted By Nikki J in September, 2023
Source: Bizrate

Overall Rating -> 8 star ratings

I am currently pleased. I like the layout of the website.

Posted By RayPoppa in January, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

I was pleased with the selection of gems, the ease of navigating, and the smooth checkout

Posted By JamesMichael781 in September, 2023
Source: Bizrate

Overall Rating -> 8 star ratings

purchased birthstones to be mounted into stud earrings as a gift for a friend's gift

Posted By MI photo in May, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

Trustworthy site. I've had several good experiences with company. Products always have met my expectations. Thank you.

Posted By Ray in February, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Had a problem ordering first time. Someone from Gem Select reached out to me and cleared problem and I made purchase.

Posted By Myrtle in February, 2024
Source: Bizrate

Overall Rating -> 9 star ratings

Overall good, shipping prices just seem a little on the high side.

Posted By Steve in August, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

I was looking for a source for affordable genuine gemstones for my grandson who is currently very interested in rocks and gems. I was quite surprised and pleased to find GemSelect and finding the right stones at the right price couldn't have been simpler.

Posted By Papa in December, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

Todo muy bien en la compra ahora esperar recibir el pedido.

Posted By MAGSMX in August, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

The website is easy to navigate and the images are incredible.

Posted By Lindsy in October, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

Good interaction with site

Posted By Brick in September, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

Great selection

Posted By GHS40 in December, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

I am excited for my first order, search tools were a great help to find the sapphire I needed for my next project! Thank you

Posted By Sue in April, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

The site is very easy to use and I will continue to shop here. The quality is superb

Posted By Genia in January, 2024
Source: Bizrate

Overall Rating -> 10 star ratings

Very excited and impressed with all your products. Keep up the good work....more different stones to choose from. I like Cabachons.

Posted By Meow in June, 2023
Source: Bizrate
STAY IN TOUCH | NEWSLETTER
*You're signing up to receive GemSelect promotional email.
Partners and Trust Payment options

Switch to Mobile Version

Copyright © 2005-2024 GemSelect.com all rights reserved.

Reproduction (text or graphics) without the express written consent of GemSelect.com (SETT Company Ltd.) is strictly prohibited.

966

Continue Shopping
Checkout
Continue Shopping
Checkout