What types of gemstones are available in 20 mm round sizes?

We offer a wide variety of 20 mm round gemstones, including Diamonds, Sapphires, Rubies, Emeralds, Amethysts, Topaz, Opals, Aquamarines, Citrines, and Garnets. Each stone is carefully calibrated for consistent sizing and quality.

Are 20 mm round gemstones suitable for jewelry making?

Yes, 20 mm round gemstones are perfect for jewelry making. Their size and shape make them ideal for rings, pendants, earrings, and bracelets. They are also commonly used in halo or pavé settings for added brilliance.

What is a calibrated 20 mm round gemstone?

A calibrated 20 mm round gemstone is pre-cut to a specific size (20 mm in diameter) to ensure uniformity. This makes them easier to set into jewelry designs and ensures a consistent look across multiple pieces.

Can I find 20 mm round gemstones in a brilliant cut?

Absolutely! Many of our 20 mm round gemstones, including Diamonds, Sapphires, and Rubies, are available in a brilliant round cut. This cut maximizes the stone's sparkle and light reflection.

Are 20 mm round gemstones available in both precious and semi-precious varieties?

Yes, our collection includes both precious gemstones like Diamonds, Sapphires, Rubies, and Emeralds, as well as semi-precious stones such as Amethysts, Topaz, Opals, Aquamarines, Citrines, and Garnets.

How do I care for jewelry made with 20 mm round gemstones?

To maintain the beauty of your 20 mm round gemstones, clean them regularly with a soft cloth and mild soapy water. Avoid exposing them to harsh chemicals or extreme temperatures. Store them separately to prevent scratches.

Can 20 mm round gemstones be customized for specific designs?

Yes, our 20 mm round gemstones can be customized to fit your unique jewelry designs. Whether you need a specific type of stone or a particular setting, we can help you create the perfect piece.

Are 20 mm round gemstones a good choice for statement jewelry?

Absolutely! The size and brilliance of 20 mm round gemstones make them an excellent choice for creating bold, eye-catching statement pieces like cocktail rings, pendants, or earrings.

Do you offer certifications for 20 mm round gemstones?

Yes, many of our 20 mm round gemstones come with certifications from reputable gemological laboratories, ensuring their quality and authenticity.

Where can I buy 20 mm round gemstones?

You can purchase our 20 mm round gemstones directly from our online store. We offer a wide selection of calibrated stones, including Diamonds, Sapphires, Rubies, Emeralds, and more, all cut to perfection for your jewelry needs.

20 mm Round Gemstones: Topaz, Opals, Garnets, Sapphires, Rubies, Calibrated 20 mm Round Gems

20 mm Round Gemstones Weight

20 mm Round Gemstones Size

20 mm Round Gemstones Clarity

20 mm Round Gemstones Price

Size Explained

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Faceted

20 mm (calibrated)

$ 210.91

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26.02ct Violet Amethyst, Round, VVS

20 mm (calibrated)

$ 181.41

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Why Buy 20 Mm Round Gemstones from GemSelect?

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GemSelect Certified Store Reviews

GemSelect: Over 22 Years in the Gemstone Business! Thank you for trusting us with your purchase!

Overall Rating -> 10

Had a great experience and the prices are great

Posted By BuBx99 in November, 2025

Source: Bizrate

Overall Rating -> 10

I love the products. I've bought them as gifts and people love my gifts

Posted By Love it! in February, 2026

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Overall Rating -> 10

The stones are very nice.

Posted By Mvk in August, 2025

Source: Bizrate

Overall Rating -> 8

The website was easy to use and there were a lot of good options, I was satisfied.

Posted By Brielly in January, 2026

Source: Bizrate

Overall Rating -> 10

My current project is something BLUE . Opal earrings with matching tennis bracelet for her wedding. The opals and sixty two sapphires VVS & VS are AMAZINGLY BEAUTIFUL. The private jewelers were impressed by the clarity and inclusion free of the sapphires . I want to say thank you for the High quality sapphires that I purchased for my daughtera's wedding.

Posted By My real name Dean or Wandering about in May, 2026

Source: Bizrate

Overall Rating -> 8

Site worked well and helped me find a rock that matched what I was looking for. Well within budget and I trust it will show up, so that's definitely positive. Not much else to it. Satisfied.

Posted By Big Ricky in May, 2026

Source: Bizrate

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