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Natural Star Gemstones

Discover rare star gemstones displaying the fascinating star effect known as asterism, perfect for collectors and unique jewelry designs.

Star Gemstones Weight
Star Gemstones Size
Star Gemstones Clarity
Star Gemstones Price

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Black Star Gemstones
Blue Star Gemstones
Brown Star Gemstones
Golden Star Gemstones
Gray Star Gemstones
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Orange Star Gemstones
Pink Star Gemstones
Purple Star Gemstones
Red Star Gemstones
Turquoise
Violet
White
Yellow Star Gemstones
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7.64ct Black Star Sapphire, Oval, Opaque

12 x 10 mm (calibrated)

$ 183.36

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6.37ct Light Brown Star Moonstone, Oval, Translucent

13.9 x 10.9 mm

$ 33.64

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9.72ct Light Coffee Brown Star Moonstone, Round, Translucent

13 mm (calibrated)

$ 51.32

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10.71ct Medium-Dark Purple Star Ruby, Oval, Opaque

12 x 11 mm

$ 169.64

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3.45ctw Dark Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 91.08

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3.22ct Deep Magenta Star Ruby, Oval, Opaque

8 x 8 mm (calibrated)

$ 180.32

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5.23ctw Navy Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 138.07

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0.58ct Night Blue Star Sapphire, Oval, Opaque

4.8 x 3.8 mm

$ 23.20

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7.88ct Cantaloupe Orange Star Moonstone, Oval, Translucent

12 x 10 mm (calibrated)

$ 37.82

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2.76ct Navy Blue Star Sapphire, Oval, Opaque

9 x 7 mm (calibrated)

$ 63.48

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8.95ct Light Coffee Brown Star Moonstone, Oval, Translucent

14 x 10 mm (calibrated)

$ 47.26

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3.93ctw Deep Navy Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 103.75

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4.43ctw Dark Blue Star Sapphire, Oval, Opaque

7 x 5.2 mm

$ 106.32

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7.89ct Medium-Light Brown Star Moonstone, Oval, Translucent

13.8 x 11.4 mm

$ 41.66

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13.46ctw Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 80.76

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3.64ct Black Star Sapphire, Pear Shape, Opaque

10.1 x 7.5 mm

$ 78.62

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6.19ct Deep Crimson Star Ruby, Oval, Opaque

9.2 x 8.6 mm

$ 118.85

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36.03ct Reddish Purple Star Ruby, Oval, Opaque

18.5 x 16.9 mm

$ 570.72

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9.13ct Deep Red Star Ruby, Oval, Opaque

13.2 x 10.1 mm

$ 109.56

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2.48ctw Navy Blue Star Sapphire, Oval, Opaque

7 x 5.3 mm

$ 68.45

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1.49ct Black Star Diopside, Round, Opaque

6 mm (calibrated)

$ 8.94

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11.04ct Cantaloupe Orange Star Moonstone, Oval, Translucent

17.6 x 10.3 mm

$ 58.30

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3.12ct Black Star Diopside, Baguette, Opaque

8 x 6 mm (calibrated)

$ 18.72

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2.74ct Black Star Sapphire, Oval, Opaque

8.2 x 6.8 mm

$ 229.32

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Why Buy Star Gemstones from GemSelect?

Natural Star Gemstones

Our natural star gemstones display the rare optical phenomenon known as asterism, where a star-shaped reflection appears across the gem’s surface. These unique stones are prized by collectors and jewelers for their striking appearance and rarity.

Star Gemstones Online

Buy star gemstones online at GemSelect with confidence. Our collection includes star sapphire, star ruby, and other rare gems with visible star effects, all available as loose stones ready for custom jewelry.

Loose Star Gemstones with Asterism

The Unique Star Effect (Asterism)

The star seen in these gemstones is caused by tiny needle-like inclusions that reflect light in a star-shaped pattern. This optical phenomenon, called asterism, becomes visible when the gemstone is cut as a smooth cabochon.

Star Sapphire Gemstones

Star sapphire is the most famous star gemstone, often displaying a clear six-rayed star across its surface. These gems are durable and popular for rings, pendants, and collector pieces.

Star Ruby Gemstones

Star rubies are rare and highly valued. When illuminated, they reveal a sharp star pattern over their deep red body color, making them one of the most sought-after asterism gemstones.

Cabochon Cut Star Stones

Star gemstones are typically cut as cabochons rather than faceted stones. The smooth, domed surface allows the star effect to appear clearly when the gem is viewed under direct light.

Loose Star Gemstones for Jewelry

Loose star gemstones are perfect for custom jewelry designs. Their distinctive optical effect makes them ideal for rings, pendants, and statement pieces that stand out from traditional faceted gems.

Collectible Star Gemstones

Many collectors seek star gemstones due to their rarity and unusual appearance. High-quality stones with centered and well-defined stars are especially desirable among gem enthusiasts.

Learn more about the properties and fascinating optical effects of gemstones on our Gemstone Optical Effects Guide.

FAQs

What are star gemstones?

Star gemstones are gems that display a star-shaped reflection on their surface. This optical phenomenon is called asterism and is most commonly seen in star sapphire and star ruby.

What causes the star effect in gemstones?

The star effect is caused by microscopic needle-like inclusions inside the gem that reflect light in intersecting lines, creating a visible star pattern when viewed under direct light.

Which gemstones show a star effect?

The most well-known star gemstones are star sapphire and star ruby, but asterism can also appear in gems like star garnet, star diopside, and occasionally in quartz.

Why are star gemstones cut as cabochons?

The cabochon cut allows the star pattern to appear clearly on the gem’s surface. Faceting would disrupt the optical effect and prevent the star from forming.

How can you see the star in a gemstone?

The star becomes visible when light hits the surface of the gemstone. Rotating the stone under a light source will make the star move across the surface.

GemSelect Certified Store Reviews

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

Overall Rating -> 10 star ratings

All items were delivered on time with all items meeting or exceeding my expectations. Cut, clarity and color were very close to the photos and description.

Posted By Bob D in December, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was easy to navigate

Posted By GemGod in July, 2025
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Overall Rating -> 9 star ratings

I was looking for a small gift for a friend- the process is the same as every other time and was very simple, and she even got her gift early! On the downside, there's no way to easily keep track of multiple Shipping Addresses, so if I want to send a gift to Friend A and to Friend B, I have to overwrite everything and it's a fair bit clunky in that regard.

Posted By Jezzi in June, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

selection was broad and the check out was quick. Great site

Posted By JC Karl in September, 2025
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Overall Rating -> 10 star ratings

I can pick and choose from large selection and find just what I need for .y projects, currently my cane.

Posted By Darkstar731 in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I was looking for high-quality amethyst on this site, and I was able to compare size, color, and weight in detail before making a purchase.

Posted By Atsuhisa in January, 2026
Source: Bizrate
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