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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

Size Explained

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Black Star Gemstones
Blue Star Gemstones
Brown Star Gemstones
Golden
Gray Star Gemstones
Green
Multicolor
Orange Star Gemstones
Pink Star Gemstones
Purple Star Gemstones
Red Star Gemstones
Turquoise
Violet
White
Yellow Star Gemstones
Single
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Lots
Faceted
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4.75ct Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 23.66

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8.47ct Brown Star Moonstone, Oval, Translucent

13.3 x 10 mm

$ 37.12

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7.26ct Brown Star Moonstone, Oval, Translucent

11.9 x 9.4 mm

$ 31.81

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4.46ct Blue Star Sapphire, Round, Opaque

9.5 mm (calibrated)

$ 97.72

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4.04ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 88.53

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4.23ct Black Star Sapphire, Oval, Opaque

9.4 x 7.9 mm

$ 75.84

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24.21ct Red Star Garnet, Oval, Opaque

16.6 x 13.9 mm

$ 23.87

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4.23ct Black Star Sapphire, Oval, Opaque

10.4 x 7.6 mm

$ 75.84

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2.61ct Black Star Diopside, Oval, Opaque

8 x 6 mm (calibrated)

$ 13.00

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6.77ct Brown Star Moonstone, Oval, Translucent

13.7 x 10.8 mm

$ 22.25

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9.28ct Black Star Diopside, Round, Opaque

11 mm (calibrated)

$ 46.21

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14.23ct Red Star Garnet, Oval, Opaque

11.3 x 11.6 mm

$ 14.74

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3.95ct Black Star Sapphire, Oval, Opaque

10 x 8 mm (calibrated)

$ 70.82

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12.12ct Gray Star Sapphire, Oval, Opaque

12.3 x 11.4 mm

$ 464.75

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3.16ct Red Star Ruby, Oval, Opaque

10.6 x 8.1 mm

$ 50.36

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3.20ct Red Star Ruby, Oval, Opaque

9.7 x 7.6 mm

$ 147.78

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3.51ct Red Star Ruby, Oval, Opaque

10.2 x 9 mm

$ 55.93

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3.28ctw Blue Star Sapphire, Oval, Opaque

7.3 x 5.3 mm

$ 62.62

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6.19ct Red Star Ruby, Oval, Opaque

9.2 x 8.6 mm

$ 98.65

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2.72ct Black Star Sapphire, Oval, Opaque

8.2 x 6.4 mm

$ 40.64

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1.95ct Blue Star Sapphire, Oval, Opaque

8 x 6 mm (calibrated)

$ 44.67

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4.92ct Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 24.50

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2.97ct Red Star Ruby, Oval, Opaque

9 x 6.4 mm

$ 47.33

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165.68ct Pink Star Rose Quartz, Oval, Transparent

32.9 x 28.3 mm

$ 272.27

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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!

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I loved it! Extensive inventory, great prices, I definitely will be buying from here again!

Posted By Lex in April, 2026
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I found the filter options excellent. Yours was the third site I visited (asked chat got for reputable online sellers of loose gems) and the first I purchased from as I was able to easily find what I was looking for.

Posted By Kelly in May, 2026
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Love how easy the site is to use. Really love that the pictures are of actual product.

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Very good place to buy gemstones

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Overall Rating -> 10 star ratings

Good, hope gem quality is good and genuine

Posted By Varun in May, 2026
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I have a beautiful emerald I purchased from a company names gemselect and they are awesome! You should try them out?

Posted By Lynn in September, 2025
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