処理...

Color-Change Garnet Gems: Properties, Meanings, Value & More

カラーチェンジガーネット宝石：特性、意味、価値など

このテキストは機械翻訳されました。 オリジナルを表示しますか？

Color-change garnets are a type of gemstone in the garnet family that show different colors under different sources of light. Among color-changing gemstones, color-change garnets display the widest range of color shifts.

Are color-change garnets natural? Yep! Natural color-change garnets come in all sorts of colors.

Is color-change garnet rare? Yep, color-change garnets are among the rarest garnet varieties.

How rare is color changing garnet? It depends on the color. Most shift from red to green or brownish-green, whereas blue color-change garnets are extremely rare.

There’s more to learn, and we’ll teach you all of it in this guide to color-change garnet types, properties, prices, and more!

About Color-Change Garnet Stone

Color-change garnets are semi-precious gemstones with a wide array of colors and color shifts. What is a color-change garnet called?

Some color-change garnets that shift from red to green can be labeled as “alexandrite-like,” but are these color-change garnets or alexandrite?

In terms of distinction, alexandrite is a chrysoberyl variety with a higher Mohs hardness (8.5) than garnet.

As garnet varieties, color-change garnets are January birthstones, traditional 2nd wedding anniversary gems, and lucky Capricorn or Aquarius stones.

Pictured above: Ring with blue topaz (center) and color-change garnets (on sides)

Color-Change Garnet Specifications & Characteristics

The complex garnet family has two overarching series: pyralspite (aluminum silicates) and ugrandite (calcium silicates).

Pyralspite contains the species pyrope, almandine, and spessartite. Ugrandite covers the species uvarovite, grossular, and andradite. Almost all garnets contain more than one species, typically species in the same series.

Most color-change garnets are in the pyralspite series, often pyrope-spessartite mixtures. That said, color-change garnets have been found in every species except uvarovite.

The most common cause of the color-change is chromium and/or vanadium impurities. Scientifically, the color-change happens because of differences in the temperature or wavelength of different light sources, and the stone’s color is the most dominant wavelength.

Color-change garnet mineral properties listed:

• Mohs hardness: 6.5-7.5

• Color: Virtually any color and multiple color-changes, including shades of red, orange, brown, green, purple, blue, and yellow

• Crystal structure: Isometric/cubic

• Luster: Vitreous, resinous, or sub-adamantine

• Transparency: Transparent to translucent

• Refractive index: 1.72-1.95 (varies by species)

• Density: 3.40-4.30 (varies by species)

• Cleavage: None

• Fracture: Conchoidal

• Streak: White

• Luminescence: Varies by species and body color

• Pleochroism: None

• Birefringence: None

• Dispersion: 0.022-0.027

• Optical phenomenon: Color-change

Types of Color-Change Garnet

Most garnet species can be color changing, but the primary ones to know are:

Color-Change Pyrope Garnets

The most common color-changing garnets are pyrope, usually pyrope-spessartite mixtures. The most notable type, discovered in the 1990s, is the predominantly pyrope-spessartite mixture that shifts from blue-green to purple, which have sold for up to $4.8 million!

Other sources for color-changing pyrope or pyrope mixtures are:

• Idaho: Pyrope-almandine, red to purple-red

• East Africa: Pastel pyrope, pink to purple

• Norway: Pyrope-almandine, violet-red to blue-green or violet to wine-red

Another notable color-change pyrope variety is Malaya garnet.

Color-Change Malaia Garnet

Malaia (or Malaya) garnets are rare pyrope-spessartite or pyralspite mixtures only mined in East Africa near Tanzania and Kenya.

They’re usually pink to orange, but color-changing types can be pink, salmon, or magenta in daylight and reddish-pink, light purple, pink, or pink-orange in incandescent light.

Color-Change Mali Garnet

Like Malaya garnets, Mali garnets only have one source in Africa: Mali. Mali garnet is a grossular-andradite mixture with yellow, green, or brown hues.

Color-changing Mali garnets appear grayish-green under fluorescent light and brown under incandescence.

Merelani Color-Change Garnet

Merelani color-change garnet comes from the Merelani Hills of Tanzania, the only source of tanzanite and its namesake, the minty-green grossular garnet variety “Merelani mint garnet.”

In contrast, many Merelani color-change garnets shift from champagne-yellow to deep wine-red.

Color-Change Rhodolite

Rhodolite garnets are a pyrope-almandine mixtures, though traces of other species like spessartite and grossular are common.

Most rhodolites are pink to reddish-purple, but color-changing rhodolites appear blue in daylight and purplish-red under incandescent lighting.

Color-Change Garnet Meaning & History

Color-change garnets possess the symbolism of all garnets: friendship, loyalty, and passion. They also carry the symbolism of color-changing gems, representing abundance, transformation, and the impermanence of life.

History

Garnets have been known for centuries, but color-change garnets were first reported in 1970.

The report came from American gemologist Robert Crowningshield, who analyzed a “rare alexandrite garnet” from Tanzania that was blue-green in daylight and purplish-red in incandescent light.

Though early interest was mainly focused on what caused the color-changes, the gem’s mainstream popularity grew in the 1980s as more sources popped up like Sri Lanka.

A major shift occurred when the first blue garnets (also color changing) were discovered in Madagascar in 1998.

Pictured above: Ring with color-changing garnet (center) surrounded by tsavorite garnets

Color-Change Garnet Healing Properties

Color-change garnets are powerful healing stones. They carry the healing properties of their respective gemstone colors and serve as chakra stones for balancing your entire energy system.

Physical Healing

Physically, color-change garnets are said to treat problems related to:

• Spine alignment

• Thyroid

• Inflammation

• Hemorrhages

• Cellular disorders

Emotional Healing

Emotionally, color-change garnet is believed to help you handle depression and self-destructive behaviors. It may also provide tranquility, emotional balance, and revitalization.

Color-Change Garnet Gemstone Properties

Though color and color-changes are key, other value factors for these garnets include cut, clarity, and carat weight.

Color

Though many variations of color shifts are available in color-change garnets, some are more valuable than others. The top value factor for color-change garnets is how strong their color-change is.

The highest value goes to more dramatic changes in different color families (e.g. a red-to-green shift is greater than a purple-to-pink color shift garnet). This dramatic shift is more common in specimens that have cool colors (e.g. blue, green, purple) in daylight.

Another factor is saturation — more saturated colors are more valuable.

Of course, rarity also matters. Blue is the rarest color-change garnet color — large specimens have sold for $1.5 million per carat!

Blue to blue-green color-change garnets that shift to red or reddish-purple under incandescence may be chromium-rich pyropes or, more often, pyrope-spessartite mixtures with small amounts of almandine and grossular.

Cut

Most color-change garnets are faceted into a variety of shapes. Lower-quality stones (e.g. highly included, fractured, weak color-change) may be cut into cabochons or carvings.

Clarity

Color-change garnets generally have Type II clarity, so some minor inclusions are common. Potential inclusions include rutile, apatite, or pyrite crystals.

In one GIA analysis, a grayish-green color-change garnet (that shifted to purplish-red in incandescent light) was found as an inclusion in a diamond!

Carat Weight

Faceted color-change garnets are typically 0.1-0.8 cts and rare above 2 carats. The largest known faceted blue-green color-change garnet is 9.5 cts.

Price-per-carat ranges increase between stones 0.5-1 ct and stones 1-6 cts.

Simulants

Since color-change garnet can be pricey, a more affordable simulant is color-change glass. One common example is the color-change glass-ceramic Nanosital®. Simulants should always be disclosed by the seller.

Color-Change Garnet Formation & Sources

Garnets usually form when high-aluminum sedimentary rocks undergo metamorphism from heat and pressure, making the former minerals inside recrystallize into new minerals like garnet. As such, garnets are most often found in metamorphic rocks like shale.

The formation of color-change garnet typically requires the presence of chromium and/or vanadium nearby.

Mining Locations

The top sources for color-change garnets are:

• Afghanistan

• Idaho, USA

• Madagascar

• Norway

• Sri Lanka

• Tanzania

Blue color-change garnets primarily come from Sri Lanka, Tanzania, and Madagascar.

Now, how much does color-change garnet cost?

Color-Change Garnet Price & Value

Color-change garnets can be pricey, but they have a broad price range. Plus, they’re less expensive than their rarer counterpart alexandrite.

Faceted color-change garnet price-per-carat ranges vary based on the strength of their color-change, which is often determined by their source, and their size:

• 0.5 to 1 carat: $80 to $2,500 per carat (Africa); $25 to $40 per carat (USA)

• 1 to 6 carats: $120 to $6,000 per carat (Africa); $35 to $80 per carat (USA)

Blue color-change garnet prices tend to be the highest, starting around $150 and reaching $10,000 or higher. Some have sold for $4.8 million!

More affordable options are color-change garnets with weaker color-changes, more visible inclusions, and/or smaller sizes.

Color-Change Garnet Care and Maintenance

Luckily, gemstone care for color-change garnets is pretty easy. You may want protective settings for jewelry, particularly a color-change garnet ring.

One sensitivity to remember is heat — keep your color-change garnets away from extreme heat, including mechanical cleaning systems.

Clean the stone with warm water, mild soap, and a soft toothbrush. Store separately from other gems to avoid scratches and out of direct sunlight to maintain the stone’s durability.

Explore the Kaleidoscopic World of Color-Change Garnets!

Can’t decide on a garnet color? Love the mesmerizing effect of color-changing jewelry like mood rings? Then color-change garnet jewelry is the perfect option for you! With plenty of color shifts to choose from, there’s a great option for any taste or style.

Buy color-change garnet gemstones today!