Star Garnet Gemstone: Properties, Meanings, Value & More

star garnet gemstoneStar garnet is a type of garnet gemstone that displays a multi-rayed light reflection on its surface resembling a star. This optical phenomenon is called “asterism.”

The stunning effect may leave you wondering: are star garnets natural? Yep, these phenomenal stones form naturally.  

Is star garnet rare? Yes, they’re pretty rare. There are only a handful of known sources for star garnets, though the Gemological Institute of America used to classify star garnets as “relatively common.” Still, star garnets are rarer than star sapphires or star rubies. 

It’s difficult to separate star garnets from Idaho, USA. This state produces enough gems to be nicknamed “The Gem State,” but star garnet holds the honor of being Idaho’s official state gemstone. Plus, Idaho star garnets are known for being the best quality. 

Today, we’ll go over everything about star garnets — properties, healing powers, history, and prices — so you can shop for these gems confidently. 

star garnet gemstone

What Is Star Garnet?

Star garnet is a semi-precious gemstone, though it can resemble the precious gemstone ruby (specifically star ruby).

As a garnet, the crystal serves as a January birthstone, Capricorn or Aquarius zodiac stone, and 2nd wedding anniversary gem.

Day-of-the-week phenomenal birthstone lists — yes, that’s a real thing — designate star ruby for Wednesday, but star garnet can be a more affordable alternative. 

Shifting gears a bit, how does star garnet get its star? Of the 60 gems that can display asterism, most owe the effect to specific types of inclusions. 

The inclusions, usually rutile or asbestiform minerals, are often made up of tiny fibers in dense, parallel bunches. They can also be feathers, veils, or hollow tubes, as long as they’re parallel. Light reflects from the inclusions, forming parallel lines or “rays” of light. 

Star Garnet Specifications & Characteristics

The garnet mineral family is complex but has some overarching categories. The two main gem series (containing three species each) are pyralspite — pyrope, almandine, and spessartite — and ugrandite — uvarovite, grossular, and andradite. 

Star garnets fall under the almandine species or pyrope-almandine hybrid species, lending them the nickname “asteriated almandine.” 

Almandine is the most common garnet species. Pyrope is a magnesium aluminum silicate, while almandine is an iron aluminum silicate. Pyrope-almandine garnets have the signature dark red coloring tied to garnet

Most star garnets are dark in color, often a dark purplish-red. 

Here are the remaining star garnet properties:

  • Mohs hardness: 7.5

  • Color: Shades of red to purple, including brownish-black, reddish-black, or blackish-purple

  • Crystal structure

  • Luster: Vitreous (glassy)

  • Transparency: Subtranslucent to opaque

  • Refractive index: 1.72-1.94

  • Density: 4.07-4.76

  • Cleavage: None

  • Fracture: Conchoidal

  • Streak: White

  • Luminescence: None

  • Pleochroism: None

You’ll often hear “star” stones discussed alongside “cat’s eye” stones — but is there a cat’s eye garnet?

cat's eye garnet vs star garnetPictured above: "Cat's eye" effect shown in chrysoberyl

Star Garnet vs. Cat’s Eye Garnet

Star garnets, while somewhat rare, are more common than cat’s eye garnets. Cat’s eye garnets display a similar optical effect called “chatoyancy,” exhibiting a single line of reflected light resembling a cat’s eye. 

If only one of the rays on a star garnet is strong and the rest are weak, this can create the illusion of a single-rayed “cat’s eye” stone instead. The majority of cat’s eye garnets are actually cut from star garnet rough. 

Moving from mix-ups into the metaphysical, let’s look at star garnet’s symbolism next. 

Star Garnet Meaning & History

All garnets symbolize friendship, protection, and passion. Star garnet specifically also represents new perspectives and fresh starts. 

Asteriated gems possess their own spiritual meaning. Historically, folks were often superstitious about star stones, believing that gazing into them caused hypnotic effects. 

Most of the superstition surrounding was positive, though. In Asian cultures, the stones are considered good luck. Others believed the stones help you maintain faith and protect you from evil. 

In fact, gems with asterism like star garnet have been around for centuries. 

History

People have known about asteriated stones for over 2,000 years. The earliest record is a description of “Asterios” from ancient Egyptian author Dionysius Periegetes around 100 BC. 

Another early mention came from famous ancient Roman scholar Pliny the Elder, who discussed an Indian star stone he dubbed “astrion” around the 1st-century AD. This stone was likely a moonstone

However, the only known star stones for centuries were corundum (ruby or sapphire) and feldspar varieties like moonstone and sunstone

Star garnets wouldn’t show up on the jewelry scene until the late 1800s. 

Pictured above: Digging for Emerald Creek Star Garnets, circa 1960s - Fernwood, Idaho | Image credit: Steve Shook, Flickr

Star Garnets in Idaho, USA

In the early 1880s, folks in Idaho, USA, started searching for garnets. Commercial production began in the 1940s, but the garnets were largely for industrial use. 

The first star garnet discovered in Idaho was found by accident. In 1937, local logger Ed “Shorty” Sexton stumbled upon the stone in the Emerald Creek area. He staked a claim on the plot, naming it “Shorty’s Diggins.” 

In 1966, Sexton leased 40 acres from the government and opened it up for public digging. The attraction saw an estimated 10,000 guests during its operation. One group included employees of the Forest Service, who encouraged Sexton’s endeavor, claiming it was the only place in the world for finding garnets that good. 

Though Sexton’s attraction is closed now, the 2009 U.S. Geological Survey commended Emerald Creek as the “the only continuously active garnet mine in the Western United States from 1940 to 2005.”

In 1967, Idaho officially designated star garnet as the state gemstone. To this day, the largest known star garnet is the “Star of Idaho,” a 3,322-carat, six-rayed gem. 

Beyond being a source of state pride for Idahoans, what is star garnet good for?

star garnet healing stone

Star Garnet Healing Properties

Like all gems, star garnet possesses metaphysical properties that make it a healing stone. Deep red star garnets, like other red gemstones, boost passion, vitality, and motivation. Purple star garnets join other purple gems in promoting spiritual wisdom and intuition. 

Star garnets are also great root chakra stones, opening this energy center to bring you balance, stability, and a foundation for personal growth. 

What about physical and emotional healing?

Physical Healing

Purported physical benefits of star garnet include treating:

  • Low libido

  • Slow metabolism

  • Poor blood circulation

  • Heart problems

  • Poor nutrient absorption

Red star garnets have long been tied to the circulatory system and heart in various cultures. 

Emotional Healing

Emotionally, star garnets are believed to help you move past outdated or unhelpful thought patterns and beliefs, opening the door for happier, uplifting outlooks. 

The stone is also said to improve creativity and ingenuity, helping you pursue your curiosity with confidence instead of being held back by self-doubt.

purple star garnet gemstone cabochon

Star Garnet Gemstone Properties

Star garnet’s value depends on its color, cut, and carat weight — the standard value factors. Valuing star garnets is unique, however, in that the number of “rays” on the stone also affects its value. We’ll also touch on synthetics and simulants.

Color

Color isn’t the number-one value factor for star garnets, but it can affect the stone’s worth. The most valuable color is a bright red star garnet. 

More desirable hues are purples and reds, while stones with brown or black hues are less valuable. Most star garnets are dark burgundy or blackish-red. 

Number and Brightness of Rays

Arguably, the most important factor for star garnet’s value are the rays. The stone can have a 3-rayed, 4-rayed, or 6-rayed star, but 6-rayed stars are the rarest and more valuable. 

Idaho and India are currently the only known sources of six-rayed star garnets. 

Additionally, the rays’ reflection should be bright enough to be an obvious “star.” Specimens can have multiple rays, some brighter than others, but the most valuable options are evenly bright, 6-rayed star garnets.

Pro tip: Always look at the stone under sunlight and other types of direct, bright lighting before buying if you can.

The asterism in star garnets can be caused by rutile inclusions or inclusions of asbestiform minerals like amphibole or pyroxene. 

Cut

Star garnet cannot be faceted — otherwise, you’ll lose the optical effect. 

Instead, star garnet is almost exclusively cut into cabochons. It takes a lapidarist with lots of skill and expertise to properly cut the stone so it ends up with a visible, centered star. 

Carat Weight

Star garnets can be quite large, but their quality typically dips with higher carat weights. Good-quality star garnets over 10 carats are scarce and valuable, but weights under 10 carats won’t significantly change the price-per-carat.

Synthetics & Simulants

Truly synthetic star garnets aren’t common, but stones may be treated to pass as “star” stones.

Typically, the sellers will simulate asterism by scratching parallel lines on the surface. One example is 8-rayed (or more rays) “star garnets” created with this method, as natural star garnets with over 6 rays are currently unknown. 

To tell apart these “fake” star garnets, look for:

  • Too many rays

  • Asymmetrical rays

  • Superficial rays (lack depth, only on surface)

Back to the real deal, how does star garnet form? 

huge red star garnet gemstone

Star Garnet Formation & Sources

Star garnets form under typical almandine garnet formation conditions: high temperature and high pressure surrounding rocks that hold the minerals inside. 

While many garnets form in metamorphic rocks, almandines and pyropes often form in igneous rocks like peridotite or granite. 

In Idaho, star garnets are found in mica schists, pegmatites, and other types of schists. The majority of Idaho’s garnets actually end up in placer deposits surrounded by gravel after the garnets separate from weathered rocks. 

Mining Locations

Where can you find star garnets? The only significant sources of star garnets are India and Idaho, USA. You can even rockhound for star garnets in the Emerald Creek Garnet Area of Idaho, which is currently the only place worldwide that allows visitors to dig for the stones. 

The only other deposits of star garnets are in Russia, China, Brazil, and North Carolina, USA. Still, India and Idaho are the only sources that have produced commercial quantities of star garnets and the only sources for six-rayed star garnets.

Thinking of browsing some star garnet for sale? Then let’s talk about what prices to expect. 

black star garnet gemstone earrings

Star Garnet Price & Value

Star garnet prices mostly depend on the number of rays reflected. Virtually all stones will be cut as cabochons. 

The most affordable option is a star garnet with a 3-rayed star, which goes for $20-$30 per carat. Stones with 4-rayed stars cost $30-$50 per carat, while 6-rayed stones fetch $30-$100 per carat. 

In terms of star garnet jewelry, here are the general price ranges (for items without additional gemstones or elaborate embellishments):

  • Star Garnet Ring: $20 to $200

  • Star Garnet Necklace: $30 to $250

  • Star Garnet Earrings: Around $45

Star garnets can be large, making heavier brooches, rings, and pendants. 

Because of its limited sources, you won’t see as many star garnets on wide scale markets, though online shopping will help in that regard. 

Star Garnet Care and Maintenance

Proper gemstone care for star garnet is pretty simple, since the stone is fairly hard and lacks cleavage. You may want protective settings for star garnet rings. 

You can clean star garnet by gently scrubbing it with a soft toothbrush that’s been dipped into a mixture of warm water and mild soap. Rinse away any soap residue, then dry it with a soft, microfiber cloth. 

Store away from other gems to avoid scratches. 

purple pink star garnet gemstone

Reach for the Stars with Star Garnet!

Star garnet may be a lesser-known type of garnet, but it’s wholly unique in its optical effect and healing powers. The color is subtle enough to complement almost any outfit, its shine will certainly turn heads. If you’re looking for a confidence-boosting stone with regality for days, let star garnet light the way!

Buy star garnet gemstones today!

Was this article helpful?

Search the Gemstone Encyclopedia

A-Z Of Gemstones

A-Z Of Gemstones

A-Z Of Gemstones
377 articles
Additional Gemstone Information

Additional Gemstone Information

Additional Gemstone Information
60 articles
Did You Know?

Did You Know?

Did You Know?
78 articles
Drawing Design Awards

Drawing Design Awards

Drawing Design Awards
2 articles
Gem Rock Auctions Verified Sellers

Gem Rock Auctions Verified Sellers

Gem Rock Auctions Verified Sellers
3 articles
Holistic Gemstone Information

Holistic Gemstone Information

Holistic Gemstone Information
34 articles
How To's

How To's

How To's is where you will find helpful articles from gem Rock Auctions on how to cut gemstones, select gemstones and buy gemstones.
9 articles
News

News

News and events on Gem Rock Auctions
48 articles
Technical Information on Gemstones

Technical Information on Gemstones

Technical Information on Gemstones
30 articles