X
Gemstone Search

Your Details

Please fill in your email address

Please fill in a password

Forgot your password?

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
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

3.97ct Purple Star Ruby, Oval, Opaque

10.1 x 9 mm

$ 76.22

View Details

3.63ct Red Star Ruby, Oval, Opaque

9.7 x 7.4 mm

$ 69.70

View Details

3.50ct Black Star Sapphire, Oval, Opaque

9 x 7 mm (calibrated)

$ 63.00

View Details

2.50ct Purple Star Ruby, Oval, Opaque

8.9 x 7.7 mm

$ 139.10

View Details

4.24ct Red Star Ruby, Oval, Opaque

8.8 x 8.2 mm

$ 81.41

View Details

4.05ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 96.23

View Details

5.55ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 146.52

View Details

1.40ct Black Star Diopside, Oval, Opaque

7.9 x 5.7 mm

$ 8.40

View Details

4.08ct Black Star Sapphire, Oval, Opaque

10 x 8 mm (calibrated)

$ 73.44

View Details

4.75ct Purple Star Ruby, Oval, Opaque

9.7 x 7.5 mm

$ 264.29

View Details

4.64ct Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 23.20

View Details

15.77ct Brown Star Sunstone, Oval, Opaque

17.3 x 14 mm

$ 157.70

View Details

9.27ct Black Star Diopside, Round, Opaque

12 mm (calibrated)

$ 55.62

View Details

7.94ct Black Star Diopside, Round, Opaque

11 mm (calibrated)

$ 47.64

View Details

6.23ct Purple Star Ruby, Oval, Opaque

12 x 10 mm (calibrated)

$ 346.64

View Details

4.13ct Red Star Ruby, Oval, Opaque

7.9 x 7.2 mm

$ 79.30

View Details

1.55ct Black Star Diopside, Oval, Opaque

8 x 6 mm (calibrated)

$ 9.30

View Details

3.01ctw Blue Star Sapphire, Oval, Opaque

7 x 5 mm (calibrated)

$ 79.46

View Details

21.47ct Yellow Star Sapphire, Oval, Opaque

16.6 x 13.8 mm

$ 231.88

View Details

4.94ct Black Star Diopside, Oval, Opaque

11 x 9 mm (calibrated)

$ 24.70

View Details

5.27ct Red Star Ruby, Oval, Opaque

9 x 9 mm (calibrated)

$ 101.18

View Details

7.62ct Brown Star Moonstone, Oval, Translucent

14.6 x 11.6 mm

$ 40.24

View Details

5.59ct Black Star Sapphire, Oval, Opaque

11.2 x 8.5 mm

$ 134.16

View Details

4.93ct Brown Star Moonstone, Oval, Translucent

12 x 8.4 mm

$ 26.03

View Details

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

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

Very good.

Posted By Tommy in December, 2025
Source: Bizrate

Overall Rating -> 8 star ratings

I've purchased things from GemSelect before. What you see is what you get, which is not always the case with gem sites online. You can find some good value with gem select, and I will buy from them again.

Posted By Meyeusername in March, 2026
Source: Bizrate

Overall Rating -> 10 star ratings

It was good. There was a large selection at prices I could afford.

Posted By Zorah in February, 2026
Source: Bizrate

Overall Rating -> 9 star ratings

It was a good experience looking for and finding a nice amethyst stone

Posted By N/a in May, 2025
Source: Bizrate

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
Enlarged Gemstone Image