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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
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Black Star Gemstones
Blue Star Gemstones
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Gray Star Gemstones
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Orange Star Gemstones
Pink Star Gemstones
Purple Star Gemstones
Red Star Gemstones
Turquoise
Violet
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Yellow Star Gemstones
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2.08ct Black Star Diopside, Oval, Opaque

8 x 6 mm (calibrated)

$ 12.48

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3.95ct Black Star Sapphire, Oval, Opaque

9.2 x 7.8 mm

$ 85.32

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6.26ctw Deep Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 135.22

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5.24ct Reddish Purple Star Ruby, Oval, Opaque

11 x 8.6 mm

$ 83.00

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1.48ct Black Star Diopside, Oval, Transparent

8 x 6 mm (calibrated)

$ 8.88

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8.87ctw Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 53.22

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26.72ct Mahogany Red Star Garnet, Oval, Opaque

19.5 x 13.2 mm

$ 33.35

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6.06ct Medium Red Star Ruby, Oval, Opaque

11.7 x 9.5 mm

$ 95.99

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34.34ct Black Star Sapphire, Oval, Opaque

20.2 x 16.8 mm

$ 535.70

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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

This is the first time I have used this site. I was dissatisfied with the quality of gems and supplies elsewhere and decided to try GemSelect. They are awesome! I was thrilled to see the variety and the great web performance. There was the ability to search for information as well as gems. Things like the clarity rating system and caret weight of the gems. I have always loved making things and I have just started to make jewelry as a business. However I have never made a ring before and have always wanted to. On GemSelect I was able to find good quality gems to use in my creations. I am so glad the website is so easy to use. Thank you GemSelect.

Posted By PickyShopper in April, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

Love, and have always loved, your website.

Posted By Aberabic in July, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

Enjoy every moment

Posted By Ferns in October, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

The citrine gems are beautiful. I appreciated that each stone was individually shown on the website so I could see exactly what I was getting. No mystery person selecting random stones for me. The documentation included with each gem was high quality as well. Great price and arrived as expected.

Posted By Jen in December, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

It was all good

Posted By Debsarabs in February, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

Great selection. Maybe too great i kept adding and deleting stuff because i found better looking ones

Posted By Edsor works in October, 2025
Source: Bizrate
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