90,000+Happy Customers
20+Years
WorldwideShipping
Cart
Free Report Included
Worldwide Shipping
30 Day Returns
Help Center Shipping Payment and Checkout Returns Certificates Contact Us
Home Gemstones Star Gemstones

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

Choose Size or Size Range
For Example: 6-7
For Example: 8-9
Bi-color
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
Pairs
Lots
Faceted
Cabochons
X
Clear All

3.95ct Black Star Sapphire, Pear Shape, Opaque

10 x 8.4 mm

$ 70.82

View Gem

4.54ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 89.53

View Gem

6.92ct Black Star Diopside, Oval, Opaque

12 x 10 mm (calibrated)

$ 34.46

View Gem

9.28ct Gray Star Sapphire, Round, Opaque

12 mm (calibrated)

$ 355.85

View Gem

3.81ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 75.14

View Gem

3.31ct Red Star Ruby, Oval, Opaque

8.5 x 7.8 mm

$ 52.75

View Gem

1.47ct Black Star Diopside, Oval, Opaque

8 x 6 mm (calibrated)

$ 7.32

View Gem

0.61ct Blue Star Sapphire, Oval, Opaque

6 x 4.2 mm

$ 20.25

View Gem

4.88ctw Blue Star Sapphire, Round, Opaque

7 mm (calibrated)

$ 101.58

View Gem

7.62ct Brown Star Moonstone, Oval, Translucent

14.6 x 11.6 mm

$ 33.40

View Gem

5.35ct Gray Star Sapphire, Oval, Opaque

9.5 x 9.1 mm

$ 186.50

View Gem

17.67ct Purple Star Ruby, Oval, Opaque

15.4 x 12.8 mm

$ 232.31

View Gem

2.86ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 62.67

View Gem

4.34ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 95.10

View Gem

2.44ct Blue Star Sapphire, Oval, Opaque

8 x 6 mm (calibrated)

$ 55.89

View Gem

8.09ct Black Star Diopside, Round, Opaque

11 mm (calibrated)

$ 40.29

View Gem

4.94ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 108.25

View Gem

5.83ct Yellow Star Moonstone, Oval, Translucent

13.2 x 10.6 mm

$ 25.55

View Gem

13.26ct Red Star Garnet, Oval, Opaque

13.4 x 11.5 mm

$ 13.08

View Gem

4.18ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 91.59

View Gem

9.59ct Red Star Ruby, Oval, Opaque

13 x 9 mm (calibrated)

$ 147.10

View Gem

13.67ct Purple Star Ruby, Oval, Opaque

16.2 x 13.3 mm

$ 179.72

View Gem

1.85ct Blue Star Sapphire, Oval, Opaque

8 x 6 mm (calibrated)

$ 61.42

View Gem

4.02ct Purple Star Ruby, Oval, Opaque

8.5 x 7.6 mm

$ 185.65

View Gem

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 -> 8 star ratings

It was a good interaction I got a good gemstone for cheap

Posted By Jon in December, 2025
Source: Bizrate

Overall Rating -> 9 star ratings

Nothing bad to report. Everything is as expected. The gems and the price are all very good.

Posted By Dafanatic in August, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

I have been very happy with my prior purchases and enjoy the website experience.

Posted By Trouble in November, 2025
Source: Bizrate

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

IT WAS GREAT SIMPLE I WAS ABLE TO MAKE AN ACCOUNT EASY AND WAS ABLE TO FAVORITE ALL OF MY FINAL SELECTED GEMS, I JUST LOVE IT.

Posted By YE in October, 2025
Source: Bizrate

Overall Rating -> 10 star ratings

hassle free experience.

Posted By Jhidron in October, 2025
Source: Bizrate
Enlarged Gemstone Image