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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.

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11.42ct Purple Star Ruby, Oval, Opaque

13 x 10.6 mm

$ 150.14

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12.90ct Purple Star Ruby, Oval, Opaque

15.4 x 12.8 mm

$ 169.60

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165.68ct Pink Star Rose Quartz, Oval, Transparent

32.9 x 28.3 mm

$ 272.27

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3.09ctw Blue Star Sapphire, Oval, Opaque

7.2 x 5.4 mm

$ 70.78

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4.45ct Purple Star Ruby, Oval, Opaque

10.3 x 7.6 mm

$ 70.92

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4.40ct Red Star Ruby, Oval, Opaque

9.4 x 8.3 mm

$ 58.43

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12.24ctw Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 50.80

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9.42ct Brown Star Moonstone, Oval, Translucent

12.9 x 10.6 mm

$ 28.15

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3.81ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 75.14

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4.24ct Red Star Ruby, Oval, Opaque

8.8 x 8.2 mm

$ 67.57

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22.76ct Purple Star Ruby, Oval, Opaque

17.9 x 15.4 mm

$ 299.23

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3.94ct Purple Star Ruby, Oval, Opaque

10 x 8.8 mm

$ 62.79

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4.92ct Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 24.50

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24.55ct Purple Star Ruby, Oval, Opaque

17.3 x 14.7 mm

$ 322.76

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25.16ct Purple Star Ruby, Oval, Opaque

18 x 15.2 mm

$ 330.78

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7.12ct Black Star Sapphire, Oval, Opaque

11.2 x 9.8 mm

$ 141.83

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27.24ct Purple Star Ruby, Oval, Opaque

18.2 x 15.4 mm

$ 358.13

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5.42ct Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 26.99

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7.80ct Brown Star Moonstone, Oval, Translucent

13.5 x 10.7 mm

$ 34.18

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13.31ct Red Star Garnet, Oval, Opaque

14 x 12 mm (calibrated)

$ 13.13

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5.16ct Yellow Star Moonstone, Oval, Translucent

14 x 10 mm (calibrated)

$ 20.56

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11.62ct Red Star Garnet, Oval, Opaque

13 x 11 mm (calibrated)

$ 11.45

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3.68ct Red Star Ruby, Oval, Opaque

9 x 7 mm (calibrated)

$ 58.65

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11.15ct Purple Star Ruby, Oval, Opaque

13.2 x 11.4 mm

$ 146.59

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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.

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