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How to Find Out the MM Measurements of a Diamond BEFORE You Shop for a Ring Setting or Ring Mount

Obtaining your diamond measurements in mm (millimeters) is the BEST way to determine whether a diamond will fit in a setting.

Most diamonds which you can purchase loose will have the mm measurements printed right on the diamond report or diamond certificate.

How to Match a Diamond with a Ring Mounting

To best help you successfully match your diamond with a ring mount in which it can be set securely, your first step in shopping for a diamond for a ring setting you like is to obtain the EXACT diamond measurements in millimeters (mm), and NOT exact carat weight, of the diamond you have, or are going to buy. All of the ring settings we offer have exact mm diameter measurement and shape requirements on the product page.

If you have your stone's mm measurements available and need help confirming whether your stone can be set securely in a given ring, please contact us.

What if I Have a Family Heirloom Diamond?

If you do not have a diamond report or appraisal for your diamond, measuring a diamond is fast and simple for any talented jeweler, who also sets gemstones, to do for you.

Just ask your jeweler who is going to be setting your diamond, to measure the EXACT millimeter diameter measurements of your diamond so that you will have this important information.

What is the Difference Between mm (Millimeters) and Carat Weight of a Diamond?

A diamond's CARAT weight measurement does NOT provide definite information as to whether a stone can be set securely in a ring setting.

Diamond measurements in mm (millimeters) are the way diamonds are classified in the jewelry trade for purposes of matching a diamond to a particular setting so that the stone can be set securely.

- Millimeters are a LINEAR measurement, like inches, feet, or centimeters.

- Carats are a WEIGHT measurement, like pounds or ounces.

To understand the difference between carat WEIGHT and diamond mm (millimeter) MEASUREMENT, consider the following scenario...

If you were asked to go out and buy clothes for someone you had never seen and you only knew that they weigh 100 pounds, what size clothing would you buy for that person? A 100 pound person could be 5 feet tall or 6 feet tall. Unless you also knew their height measurement, it would be impossible to guess a correct clothing size based on knowing their weight alone!

You can think of a ring setting as the clothing for a diamond, which is why the required measurements for a stone to be set securely are noted in the item description for every ring setting and ring mount in our collection.

Should You Buy A Stone From Us?

We stock thousands of loose fine colored gemstones, loose old natural diamonds, and lab created diamonds, which we can set for you in one of our ring settings. Mounting (setting) a diamond or gem purchased from us in any of our ring setting designs is always done by our expert jewelers at no charge to you.

Find Loose Diamonds for Sale and Loose Old Diamonds for Sale.

Due to insurance limitations, our jewelers can not set diamonds or other loose gems provided to us by a customer. If you plan to purchase a ring mount with no stone from us for a diamond you already own, you will want to find a talented and reputable jeweler who guarantees his work to set your diamond for you.