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Buy Square Shape 12x12 mm Gems

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Square Shape 12x12 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 Square shapes, facet cut and cabochon gems available now in 12 mm 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 meant nor 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 around 0.3 mm or slightly higher even. This small variance can usually be accommodated for 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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Thank you for trusting us with your purchase!

Overall Rating -> 10 star ratings

It was a nice and easy process throughout! The website is simple and well made I found everything I needed quickly. I needed some emeralds of a certain size for my custom engagement ring but they only had 3 available on the website, So bought the available ones and reached put to customer service to see if they have any more and they messaged me back within minutes with a list of similar sized emeralds that were not on the site! I quickly purchased my remaining emerald and they added it to my first order! I am more than pleased with the experience and I will be recommending them to anyone in the market for gems! 10/10

Posted By Marty in July, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

I have been shopping with Jim select for quite a few years. The descriptions of the gyms are accurate and the selection is very broad. Anyone looking for loose gyms, this is the place to go. Check out is easy.Pricing is very reasonable.

Posted By Ronald in January, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

It’s always awesome and easy to do

Posted By Dustyrose in July, 2022
Source: Bizrate

Overall Rating -> 9 star ratings

I got my order early and was happy with the stones, Just wish they were a little bigger, very nice quality

Posted By Wolf in January, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

My last experience was good, in fact every experience I have had with them has met my expectations or surpassed them. These are really good people to work with.

Posted By Spinach in May, 2023
Source: Bizrate

Overall Rating -> 9 star ratings

I've been collecting gemstones for a while now so I wad excited that I found a relatively cheap site to gems from. When I opened to package i was a little surprised and how small they were but it's literally marketed for jeweler's so I understand why my little square cut sapphire is the size of a crumb, but all in a ll I'm very happy with what I ordered.

Posted By Kelsey in October, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

Everything was straight forward as always. I've shopped here many times over the years and know where things are. Everything was quick and easy to find. The website is organised well. Great shopping experience.

Posted By Konstantin Marchenko in January, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

The merchant responded quickly to me questions. Wish I could afford more...haha

Posted By Carolina Girl in December, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

Gems look fantastic and just as advertised.

Posted By Jess in October, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

It was great i bet there is a way to just look for blue gemstones but I found em so it doesn't matter.

Posted By Aaron in October, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

Every aspect of the purchase from selection to receipt was easy and quick. Sometimes I go through my items just to admire my purchase.

Posted By Old Salt in February, 2023
Source: Bizrate

Overall Rating -> 8 star ratings

Excellent product selection with easy to use sorting functions. Gem pricing is also competitive.

Posted By Travelnman in February, 2023
Source: Bizrate

Overall Rating -> 10 star ratings

Great selection and the website is easy to navigate

Posted By Ethan in September, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

Another great purchase. I just received my 3rd order and have another coming soon. Won't buy anywhere else!

Posted By Beth P. in June, 2022
Source: Bizrate

Overall Rating -> 10 star ratings

Bought my first set of gemstones of gemselect to start off my collection. Everything is what it says it is, 100% legit. They even send u a pamphlet for every gem you order even the $1 ones lol. Good store.

Posted By SuperBee in March, 2023
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

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