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Buy Marquise Shape 18x9 mm Gems

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Marquise Shape 18x9 mm Gems

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

No comment other than can you add more beads or drilled spheres to your inventory. Finding high quality beads on the internet is almost impossible. Buying from your site i fell confident what i am getting is real.

Posted By Mark in April, 2022
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Overall Rating -> 9 star ratings

The process was made very streamlined and the layout is very intuitive to navigate.

Posted By Ig in February, 2022
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Overall Rating -> 10 star ratings

It was all good

Posted By Jimy in November, 2021
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Overall Rating -> 10 star ratings

I have ordered many many gems over the years from them and I am always VERY happy!! And if I wasn't they do accept returns which is a great peace of mind.

Posted By SaraP in July, 2021
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Overall Rating -> 8 star ratings

I am always looking for good quality stones

Posted By Nathan in November, 2021
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Overall Rating -> 10 star ratings

Found what I wanted right away and bought them.

Posted By Kris in March, 2022
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Overall Rating -> 10 star ratings

I had problems with PayPal. My customer service rep, Thomas, did a great job in shepherding me through the process. I ended up purchasing three stones, due to Thomas good customer service. Thomas deserves a raise and a week's vacation.

Posted By WildWillie in April, 2022
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Overall Rating -> 10 star ratings

Good experience

Posted By Kathryn in September, 2021
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Overall Rating -> 10 star ratings

Awesome experience

Posted By NZ Kiwi in February, 2022
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Overall Rating -> 10 star ratings

I bought some opals and got a really good deal.

Posted By C0rt3x in June, 2021
Source: Bizrate

Overall Rating -> 10 star ratings

gem selection is pretty great, prices are unbelievably low, however the cut of some gems is questionable at best. you have to dig for the good ones, but it’s worth it for the price

Posted By Katie in September, 2021
Source: Bizrate

Overall Rating -> 10 star ratings

I have been looking at the website for a few days, educating myself about Sapphires and other gems. I want to have earrings made as a gift for someone. I bought a air of gemstones for myself today. They look beautiful in the photo.

Posted By Ozwiena in October, 2021
Source: Bizrate

Overall Rating -> 7 star ratings

It would be nice if free shipping was offered for high dollar total orders, also the site could be easier to navigate if it was left to search all products at once instead of certain collections. Although very helpful adding a feature to make it easier to search all your inventory is better than hunting and weeding through multiple pages and links.

Posted By Snifferpippets in January, 2022
Source: Bizrate

Overall Rating -> 9 star ratings

The site it's self looks fairly plain and simple but the wide variety of stones with high quality photos and price ranges made finding a beautiful stone in my price range was extremely easy.

Posted By Randy in July, 2021
Source: Bizrate

Overall Rating -> 10 star ratings

Great products. I make custom jewelry and gemselect let’s me provide a variety of quality stones to my customers to choose from. Thank you.

Posted By Austin in June, 2021
Source: Bizrate
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Size and Weight

Gems are always measured in Millimeter (mm)

Dimensions are given as;
length x width x depth,
except for round stones which are;
diameter x depth

Select gems by size, not by weight!
Gem varieties vary in density, so carat weight is not a good indication of size

Note: 1ct = 0.2g

Size Comparison Chart