Color Change Garnet Value, Price, and Jewelry Information

This round, brilliant-cut color change garnet shows brown in compact fluorescent lighting, purple in daylight, and hot pink in incandescent lighting. 0.65 cts, 5.45 mm, Tanzania. © Dan Stair Custom Gemstones. Used with permission.

Color Change Garnet

Any stone that changes color under different types of light is a rare treat for collectors. Color change garnets show the widest range of transformations in the gem world, with almost any hue possible.

Color Change Garnet Value

The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.

Garnet Value via Gem Price Guide

Almandine

Top Color: oR, R, PR, rP 6/4
Almandine All sizes
to /ct

Almandine/Pyrope Blend ("Mozambique")

Red-Brown Colors
"Mozambique" All sizes
to /ct

Rhodolite (Almandine/Pyrope Blend)

Fine Color: rP, PR 6/5
Rhodolite .5 to 1 carat 1 to 10 carats 10 carats plus
Faceted to /ct to /ct to /ct
Cabochons to /ct to /ct to /ct

Andradite

Fine Color: G 5/4
Andradite All sizes
to /ct

Demantoid

Demantoid to 1 carat 1 to 3 carats
to ,200/ct to ,000/ct

Grossular

Grossular .5 to 1 carat 1 to 5 carats 5 carats plus
Mint Green (Merelani) to /ct to /ct to /ct
Yellow/Orange to /ct to /ct to /ct
Yellow/Green to /ct to /ct to /ct
Other colors /ct /ct to /ct

Hessonite

Fine Color: yO 4/5
Hessonite Garnet All sizes
to /ct

Tsavorite

Fine Color: G 6/5
Tsavorite .5 to 1 carat 1 to 2 carats 2 carats plus
Faceted to /ct to ,500/ct to ,000/ct

Mali Garnets (Andradite/Grossular Blend)

Mali Garnet All sizes
to /ct

Malaya (Malaia) Garnets

Malaya Garnet .5 to 1 carat 1 to 5 carats 5 carats plus
to /ct to /ct to /ct

Pyrope

Fine Color: R 6/5
Pyrope 1 carat plus
/ct

Chrome Pyrope

Chrome Pyrope All sizes
to /ct

Spessartite

Spessartite Reds .5 to 3 carats 3 to 6 carats
Little 3 Mine to ,000/ct to ,000/ct
African to /ct to /ct
Darker reds to /ct

Mandarin

Fine Color: O 4/5
Mandarin Orange All sizes
to ,200/ct

Uvarovite

Uvarovite 10 carats plus
Druzy to /ct

Star Garnet

Star Garnet All sizes
6 ray star to /ct
4 ray star to /ct

Color Change

Color Change .5 to 1 carat 1 to 6 carats
Africa to ,500/ct to ,000/ct
US to /ct to /ct

Cabochons

Cabochons All Sizes
Common red to purple to /ct

Color Change Garnet Information

Data Value
Name Color Change Garnet
Is a Variety of Garnet
Colors Various shades of red, pink, purplish red, reddish orange, red-orange, orange, brownish orange, yellowish orange, greenish, greenish yellow-brown, brown, peach, purple, blue, blueish green, green, violet. Many possible color change combinations.
Fracture Conchoidal
Hardness 6.5-7.5
Cleavage None
Crystallography Isometric
Refractive Index See the Gem Listings for specific garnet varieties.
Birefringence None
Dispersion 0.022-0.027
Absorption Spectrum See the Gem Listings for specific garnet varieties.
Pleochroism None
Optics Isotropic. May show anomalous birefringence.
Luster Vitreous
Polish Luster Vitreous
Specific Gravity See the Gem Listings for specific garnet varieties.
Transparency Transparent to opaque
Phenomena Color change
Birthstone January
Formula See the Gem Listings for specific garnet varieties.

Trillion-cut color change garnet (brown to red), 2.41 cts, 8.66 x 8.05 x 4.59 mm, Madagascar. Photo courtesy of liveauctioneers.com and Jasper52.

Comments

Garnets belong to a complicated family, full of surprises. Color change garnets are no exception. For many years, it was commonly said that garnets come in every color of the rainbow — except blue. Recently, this has been proven false. In the 1990s, garnets that appear blue-green in daylight and purple in incandescent light were discovered in Madagascar. These stones were a mix of predominantly pyrope and spessartite.

Blue color change garnets are exceptionally rare stones. One large specimen has sold for $1.5 million per carat.

This color change garnet from Africa shifts from blue to purple. © All That Glitters. Used with permission.

How Do You Classify Color Change Garnet?

Most, but not all, garnets that display color change consist of a mix of pyrope and spessartite, such as those blue gems as well as rare but more accessible malaia garnets. However, garnets from Idaho, primarily mixtures of almandine and pyrope, occasionally show a strong color shift from red to purplish red. Mali garnets, predominantly grossular with some andradite, may also show a color change from grayish green in fluorescent light to brown in incandescent light.

Distinguishing garnet species can be difficult. Keep in mind that color change garnets aren’t a specific garnet species or limited to a specific mixture of species. These gems will display the physical and optical properties of the species or blend to which they belong. These durable stones should also receive the same care and maintenance as all other garnets.

andradite crystals - Afghanistan

These andradite crystals on matrix display an unusual color shift. Under halogen light, they appear a pastel “mint green,” but under mercury light, they appear an intense “lime green.” 9.2 x 5.2 x 3.9 cm, Ghazni Province, Afghanistan. © Rob Lavinsky, www.iRocks.com. Used with permission.

Sources

Afghanistan, Madagascar, Norway, Sri Lanka, Tanzania, and the U.S. state of Idaho have all produced color change garnets.

Rectangular radiant-cut color change garnet (brownish tan to red-purple), 1.99 cts, 8.9 x 5.8 mm, Elahara, Sri Lanka. © The Gem Trader. Used with permission.