Calibrated 18 x 13 mm Octagon Shape Natural Gemstones: GemSelect

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:

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:

Item Description
Stone Type:	Loose Citrine
Citrine Weight:	15.19 ct Citrine
Citrine Shape:	Octagon Step Cut Citrine
Citrine Size:	17.9 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:

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:

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:

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:

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:

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:

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:

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.

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Gemstone Information

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Overall Rating -> 9

GemSelect has a fantastic assortment of Semi-precious stones. I have not found any other web site with the variety you have.

Posted By RobDill in August, 2023

Source: Bizrate

Overall Rating -> 10

Was easy to search for many gems and mineral stones.Authenticity of natural stones is important, and I feel this site offers some assurance on this.

Posted By DanM in November, 2023

Source: Bizrate

Overall Rating -> 10

I enjoyed browsing though different varieties of rubies. I felt that the experience was simple and easy to navigate!

Posted By Daws in July, 2023

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Overall Rating -> 10

The website is easy to search, the variety of gems is excellent and the educational information is interesting and helpful! Love browsing and shopping the GemSelect website!

Posted By Happiness in January, 2024

Source: Bizrate

Overall Rating -> 10

The website was very easy to navigate. We appreciated the details about each gem, and the sort and search features of the website were helpful and easy to use.

Posted By AV in May, 2023

Source: Bizrate

Overall Rating -> 10

the searching format was easy to find what i needed. It helped to be able to sort Lowest price to Highest because i wasnt looking to spend too much but i did want an actual stone and not imitation.

Posted By PixelComposer in January, 2024

Source: Bizrate

Overall Rating -> 10

Convenient selection, arrival on time

Posted By Alin in February, 2024

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Overall Rating -> 10

Gem Select has gems at afffordable prices.

Posted By George in March, 2024

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Overall Rating -> 9

I have been buy from you for years

Posted By JohnA in May, 2023

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Overall Rating -> 10

first time here sooooooooooo we will seeeee!!!!! so far so good!!!!!!

Posted By Seastone 56 in October, 2023

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Overall Rating -> 10

Great experience! First time buyer

Posted By Todi89 in February, 2024

Source: Bizrate

Overall Rating -> 10

I really enjoy browsing through GemSelect. The selection is always marvelous and I love how detailed everything is described. The only thing I noticed is that when browsing through my phone, the videos of the gems do not load. If there were more videos of the gems, that would be amazing, though I understand that is a lot of work on GemSelect's part! Checking out is also very fast and easy, and I love that the return policy is very good, though I hope I don't have to use it anytime soon.

Posted By ChiChi in January, 2024

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Overall Rating -> 10

Excellent experience!

Posted By Steph in April, 2023

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Overall Rating -> 10

I purchase all of my stones from GemSelect! They're the best I've found for both selection and value.

Posted By Terry in June, 2023

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Overall Rating -> 10

The website design is a bit finicky for mobile, but Im sure its most likely just a mobile issue. Amazing selection of products, great prices.

Posted By Kuba in December, 2023

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Selected Gemstones

Gemstones A-Z

Buy Octagon Shape 18x13 mm Gems

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

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

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

Natural Citrine, Qty: 1 pc | 15.19 carat weight Citrine

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

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

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

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

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

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

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