Calibrated Size for Octagon Cut Gemstones 16x12 mm

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 16 x 12 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

Gemstone Information

Over 19 Years in the Gemstone Business!

Thank you for trusting us with your purchase!

Overall Rating -> 10

Everthing about researching and ordering from Gemselect was easy and uncomplicated. In the past I had payment problems, but your customer rep, Thomas, helped me get everything right. I will continue using Gemselet in the future for these reasons.

Posted By WildwillyfromArizona in August, 2023

Source: Bizrate

Overall Rating -> 10

Super easy to do business for great products.

Posted By BoBBy in January, 2024

Source: Bizrate

Overall Rating -> 10

Pleasant.

Posted By Mk in November, 2023

Source: Bizrate

Overall Rating -> 10

I have used this site for sseveral years now. All has been great. I started collection gems from GemSelect for years and wanted to collect at least one of most stones. I loved Safers because the mols is a 9 + and they come in every color. This is the best place to buy gems for the assortment and price. Great place to learn about gems too. Sometimes the shipping is a little on the long side. But I would give them a 9.9 out of 10 !!

Posted By Steve in July, 2023

Source: Bizrate

Overall Rating -> 10

great. thank you

Posted By Carrotroller in July, 2023

Source: Bizrate

Overall Rating -> 9

The selection and filtering is a little overwhelming, but that's only because there is so much to choose from.

Posted By Kasper in June, 2023

Source: Bizrate

Overall Rating -> 10

I have received emails for about a year and today is the condition that had me decide on the purchase

Posted By Tim in April, 2024

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

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 -> 10

I FOUND WHAT I WANT IT

Posted By GABY in March, 2024

Source: Bizrate

Overall Rating -> 10

love yall

Posted By Rock hunter in August, 2023

Source: Bizrate

Overall Rating -> 10

i love this site, the gems are always of good quality, i've been buy gifts from the site for 10 years, love it

Posted By Jf in January, 2024

Source: Bizrate

Overall Rating -> 8

I did not realize how small the stone was. I cannot use it for the project I wanted, but I am keeping the stone and tru to use it in something else.

Posted By Mark in March, 2024

Source: Bizrate

Overall Rating -> 10

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 -> 7

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.

Posted By Bobk in February, 2024

Source: Bizrate

Gemstones A-Z

Buy Octagon Shape 16x12 mm Gems

28.91 carat Oval Amethyst, loose Certified Amethyst from Brazil, Natural Untreated Gem, 21.6 x 14.5 mm

6.28 carat Yellow Citrine, Briolette loose Citrine from Brazil, Natural Untreated Gem, 14.3 mm

2.81 carat Yellow Citrine, Bullet Shape Checkerboard loose Citrine from Brazil, Natural Untreated Gem, 8 x 6.9 mm

1.99 carat Orange Zircon, Oval loose Zircon from Tanzania, Natural Untreated Gem, 8 x 5.9 mm

0.79 ct Orange Sphalerite, 5 mm Round Cut From Spain

16.71 ct Oval Fossil Coral, 17.7 x 9.7 mm From Indonesia

6.98 ct Loose Pear Dendritic Agate, 16.4 x 12.2 mm From India

1.03 carat Green Tourmaline, Emerald Cut loose Tourmaline from Mozambique, Natural Untreated Gem, 20.4 x 2.3 mm

1.22 carat Orange Hessonite Garnet, Oval loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 8 x 6.5 mm

0.88 ct Oval Chocolate Opal, 8.1 x 6.1 mm From Ethiopia

0.92 carat Orange Citrine, Marquise Cut loose Citrine from Brazil, Natural Untreated Gems, 8 x 3.9 mm

17.63 ct Fancy Boulder Opal, 23.8 x 14.9 mm From Australia

1.75 ct Loose Oval Cut Black Opal, 12.4 x 8.3 mm From Ethiopia

0.68 ct Loose Yellow Sapphire, 3.7 x 3.6 mm Princess Cut From Tanzania

20.03 ct Loose Oval Lapis Lazuli, 14.7 x 10.7 mm From Afghanistan

0.97 ct Oval Cat's Eye Moonstone, 7.7 x 5.9 mm From India

13.35 ct Black Spinel, 20.1 x 10.1 mm Baguette Rose Cut From Thailand

18.05 carat Ammolite, loose Certified Ammolite from Canada, Natural Gem, 29.9 x 16.8 mm

17.02 ct Multicolor Jasper, 24.4 x 19.8 mm Oval Cut From Indonesia

7.02 ct Pink Morganite, 10 x 11.1 mm Oval Cut From Afghanistan

1.12 carat Orange Hessonite Garnet, Emerald Cut loose Hessonite Garnet from Madagascar, Natural Untreated Gem, 7.2 x 4.8 mm

3.7 carat Yellow Citrine, Emerald Cut loose Citrine from Brazil, Natural Untreated Gem, 12 x 8.1 mm

3.1 carat Briolette Tourmaline, loose Certified Tourmaline from Mozambique, Natural Untreated Gems, 5.7 mm

2.58 carat Square Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 4.9 x 4.8 mm

0.96 ct Oval Cut Peridot, 7.2 x 5.1 mm From China

3.62 carat Marquise Cut Pyrope Garnet, loose Certified Pyrope Garnet from Mozambique, Natural Untreated Gems, 11.9 x 5.8 mm

1.31 carat Oval Ruby, loose Certified Ruby from Myanmar, Natural Gem, 7.2 x 5.2 mm

14.33 ct Round Labradorite, 15.1 mm From Madagascar

1.08 carat Trillion Rhodolite Garnet, loose Certified Rhodolite Garnet from Mozambique, Natural Untreated Gems, 5.3 x 5.2 mm

10.69 ct Asscher Cut Rose Quartz, 13.4 x 13.3 mm From South Africa

2.62 ct Pink Morganite, 13.1 x 9.9 mm Carved From Afghanistan

2.55 carat Sky Blue Topaz, Pear Shape loose Topaz from Brazil, Natural Gems, 6 x 4.2 mm

Gemstone Information

Gemstone SHOP

POLICIES

WHO ARE WE?

Gemstone EDUCATION

WE ARE LOCATED AT