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Color-Change Sapphire Gem: Properties, Meanings, Value & More

變色藍寶石寶石：特性、含義、價值等

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Color-change sapphires are gemstones in the corundum family that display different colors under different types of lighting. But are color-changing sapphires real? Shockingly, yes! (Although, they can also be created synthetically).

Sapphires can display multiple, natural optical effects including asterism (star sapphire), chatoyancy (cat’s eye sapphire), bi-coloring, and of course, color-changes.

How rare is a color-changing sapphire? They’re pretty rare, though not the rarest sapphires (that honor goes to cornflower blue and Padparadscha sapphires). Still, color-change sapphires are quite valuable!

Eager to know more about color-changing sapphires? Stick around as we uncover this gemstone’s multitude of colors, properties, prices, and more!

About Color-Change Sapphire Stone

Color-change sapphires are phenomenal precious gemstones that have different colors under different light sources like daylight and incandescent light.

What is the color-changing sapphire called? Some call alexandrite-like (red to green) color-change sapphires “alexandrium.” The main differences between color-change sapphire vs alexandrite are their species and rarity: alexandrite is a chrysoberyl variety and much rarer.

As such, you can use color-change sapphire as a more affordable June birthstone alternative to alexandrite. Of course, sapphire is already a September birthstone, as well as the 5th, 45th, and 75th wedding anniversary gem.

You can even give the traditional a modern twist with a color-changing sapphire engagement ring — after all, sapphires were the gem-of-choice before diamonds became the standard for engagement rings.

Color-Change Sapphire Specifications & Characteristics

As corundum varieties, the color-change sapphire formula is Al2O3. The stone’s base colors include virtually anything but red, which is ruby.

All corundum colors come from impurities, but gemologists think the actual color-changing effect often comes from certain impurities, notably vanadium and chromium.

The first colors appear in daylight, fluorescent light, or daylight-balanced LED light. The other colors appear in incandescent light, tungsten light, or candlelight. Many artificial lights are used today, but the initial color should be observed under sunlight.

The color-change is also different from pleochroism. Pleochroism depends on viewing angles (not type of lighting), and color-change sapphires are often also pleochroic.

Another important distinction is color-change vs bi-color sapphires.

Bi-color (or parti-color) sapphires like peacock and mermaid sapphires have two colors at the same time, similar to watermelon tourmaline. This is called “color-zoning,” where color is unevenly distributed because the color-causing elements change as the crystal forms.

Color-change sapphire properties listed:

• Mohs hardness: 9

• Color: Daylight/Fluorescent: Usually blue to violet; rarely green or red; Incandescent: Usually purple, pink, or reddish-purple; Rarely red, reddish-brown, brown, yellow-green

• Crystal structure: Hexagonal (trigonal)

• Luster: Vitreous, subadamantine, or adamantine

• Transparency: Transparent to opaque

• Refractive index: 1.757-1.779

• Density: 3.99-4.10

• Cleavage: None

• Fracture: Conchoidal

• Streak: White

• Luminescence: Fluorescence often present - Natural fancy color: red in LW-UV & red to orange in SW-UV; Natural blue: weak light red in SW-UV; Synthetic (all colors): orange to red in LW-UV & SW-UV or red in LW-UV & mottled blue in SW-UV; X-ray colors in some specimens - dull red or yellow orange

• Pleochroism: Present and strong, varies by sapphire color (see individual sapphire color guides for specifics)

• Birefringence: 0.008-0.009

• Dispersion: 0.013-0.018

• Optical phenomena: Color-changing; Very rarely combined with asterism or chatoyancy

Color-Change Sapphire History

It’s unclear when the first color-change sapphires appeared.

One of the earliest recorded color-changing gems was alexandrite, discovered in Russia in the 1830s. It set the standard for future color-changing gems, sometimes said to exhibit the “alexandrite effect.”

In fact, the first synthetic color-change sapphire was created to imitate alexandrite. These were popular in the early 1900s.

However, one fictional example precedes these: the titular Le Saphire Merveilleux, French for “The Miraculous Sapphire.”

French writer Madame de Genlis wrote this story in the 1800s about a sapphire that changed colors to indicate whether someone was adulterous, though choosing for her to wear the sapphire at day or night could skew the verdict.

According to the August 1919 edition of The Jewelers’ Circular, the fictional stone was inspired by a real color-change sapphire displayed at the South Kensington Museum in the collection of Polish nobleman Count de Walicki.

Color-Change Sapphire Healing Properties

Color-change sapphire’s meaning reflects its properties as a healing stone: the stone can symbolize and facilitate balance, transformation, and wisdom. Plus, color-change sapphires can be effective chakra stones for every chakra.

The crystal is also said to dispel anxiety, jealousy, and unhealthy attachments.

Color-Change Sapphire Gemstone Properties

Are color-change sapphires valuable? It depends on their quality.

When grading color-change sapphire value, the standard properties like color, cut, clarity, and carat weight matter, but the strength of color-change is also important — in fact, color-change strength is the top value factor.

Color

Most color-change sapphires shift from blue or violet in daylight to violet, pink, or reddish-purple in incandescent light, with most going from blue to purple.

Rarer shifts include:

• Red to brown

• Greed to reddish-brown

• Green to yellow-green

• Grayish- or greenish-blue to brownish-red

One fascinating discovery from the Gemological Institute of America (GIA) is that some orange, yellow, or pink sapphires shifted to pure orange or Padparadscha-like colors during color stability testing (a few hours under intense incandescent light).

The ideal shift is from a warm to cool color, which brings us to our next factor…

Strength of Color-Change: Percentage & Degree

The most important value factor for these gems (followed by color) is the strength of their color-change, broken down into the percentage and degree of color-change.

• Percentage: How much of the stone’s area changes color (viewed face up).

• Degree: How dramatic the difference in colors is, ideally complementary colors.

For example, blue to violet or red to purple aren’t as dramatic as shifts from green to red or violet to orange. Higher saturation also boosts value.

The percentage can reflect the stone’s value, as a sapphire with a 40 percent color-change (a little less than half of its area) will be 40 percent as valuable as an equivalent stone with a 100 percent color-change.

The degree of color-change is often expressed as weak, moderate, or strong.

Cut

Color-change sapphires are often faceted. Calibrated sizes and uniform cuts aren’t as common, but the potential shapes overlap with regular sapphires. Common ones include oval, cushion, pear, and trillion shapes.

The stones may also be cut into cabochons, particularly the very rare color-changing and asteriated or chatoyant sapphires.

Clarity

Color-change sapphire has Type II clarity, so minor visible inclusions are expected.

Potential inclusions in color-change sapphires include:

• Rutile (needles, particles, platelets, arrowheads)

• White particle clouds in stacked patterns

• Zircon crystals

• Boehmite tubules or needles

• Fingerprints, sometimes reflective & iridescent

• Two-phase inclusions

• Color-zoning, sometimes in hexagonal growth patterns

Clarity isn’t a major factor here, as eye-clean specimens are super rare.

Carat Weight

Most color-change sapphires are small (under 2 cts). The color-change strength usually diminishes in larger sizes, so a large stone with strong color-change is exceedingly valuable. Price-per-carat rates can increase above 1 carat.

Treatments & Synthetics

Treatments aren’t common for color-change sapphire, but some are fracture-filled or diffusion-treated.

More often, you’ll see synthetic color-change sapphires, usually created with the Verneuil (flame fusion) method.

How can you tell if a color-changing sapphire is real (natural) or synthetic?

1. Under a spectroscope, synthetic color-change sapphires show an absorption line at 4740.

2. Flame-fusion synthetic color-change sapphires sometimes have curved striae and air bubbles inside.

3. Flame-fusion sapphires usually glow red under a blacklight.

4. Synthetic color-change sapphires often have more “pure” colors and a more flawless appearance.

How do natural color-change sapphires form, though?

Color-Change Sapphire Formation & Sources

Color-change sapphires form just like other sapphires inside igneous or metamorphic rocks.

The only difference is that certain impurities, like chromium and vanadium, must be present to eventually cause color-changes.

Mining Locations

The top source of color-change sapphires is Tanzania. Other major sources are:

• Sri Lanka

• Kenya

• Madagascar

Minor sources include:

• Australia

• China

• Cambodia

• Nigeria

• Thailand

• USA (Montana)

Now, what is the price of color-change sapphire?

Color-Change Sapphire Price & Value

Faceted color-change sapphire price per carat ranges are broad, depending on their quality and size. How much is a carat of color-change sapphire? Let’s look at the general breakdown:

• 0.5 to 1 carat: Around $100 to $3,000 per carat

• 1 to 7 carats: Around $300 to $5,000 per carat

Many blue to violet options are around $100 per carat. Opting for synthetics can decrease the price significantly, with some as low as $2 per carat, plus rings and necklaces around $40-$80.

Color-changing star sapphire cabochons are usually about $300 per carat, though some reach over $2,000 per carat.

Color-Change Sapphire Care and Maintenance

Luckily, gemstone care for color-change sapphires is pretty easy. You can clean them with warm, soapy water and a soft microfiber cloth. Rinse well.

Just keep the stone away from:

• Extreme heat

• Extreme temperature changes

• Hydrofluoric acid

• Bleach

Store separately from other gems.

Get A Sapphire That Changes With You!

Change is inevitable, so why not embrace it? Color-changing sapphires aren’t only a cool party trick, but a reminder that it’s all about balance. With natural and synthetic options for any budget, you’re sure to find one for you!

Buy color-change sapphire gemstones today!