Blue Garnet

Blue Garnet are truly, uniquely beautiful Blue-Green (teal) gemstones recently unearthed in Tanzania’s famous Umba River Valley. Only reported in 2017, Blue Garnet is a rare and unusual sub-variety of an already rare Garnet, and despite its beauty, will always have an inadequate supply, making Blue Garnet highly collectable and very exclusive.

Hardness 7 - 7.5
Refractive Index 1.760 - 1.765
Relative Density 3.83 - 3.88
Enhancement None


Named for a dominant hue rarely seen in Garnets, Blue Garnet is an incredibly rare, undeniably beautiful, and an extremely unusual variety of Color Change Umbalite Garnet. Unlike traditional Color Change Garnets that exhibit a color change from purplish or orange red in incandescent (indoor) light to bluish or yellowish green in daylight, Blue Garnet displays an attractive color shift (a color change where the two colors are near each other on the color wheel) from blue with a hint of green (blue teal) in sunlight or candescent light, to a green with blue flashes in candlelight or incandescent light.

While Blue Garnets’ ‘blue’ is vaguely similar to the teals of Queensland Sapphire, its color shift makes its hue distinctly beautiful, highly collectable, and undeniably unique when compared to the ‘blues’ of most Sapphires as well as other blue gemstones such as Apatite, Indicolite, Kyanite, Paraiba Tourmaline, Topaz, Turquoise, and Zircon.

Good cutting accentuates the innate beauty of Blue Garnet and every gem is finished eye-clean, the highest quality clarity grade for colored gemstones, with an attractive shape and overall appearance. Blue Garnet has excellent fire and dispersion, and are mostly faceted as Ovals and Rounds, but any cut that maximizes brilliance is indicative of fine quality.

Used in adornment for over 5,000 years, Garnets were popular in ancient Egypt from around 3100 BC, being used as beads in necklaces as well as inlaid jewelry (gems set into a surface in a decorative pattern). Garnet’s many myths frequently portray it as a symbol of light, faith, truth, chivalry, loyalty and honesty.

In Judaism, a Garnet is said to have illuminated Noah’s Ark and Garnet (carbuncle) was also one of the gems in the ‘breastplate of judgment’ (Exodus 28:15-30), the impetus for birthstones in Western culture. Crusaders considered Garnet so symbolic of Christ’s sacrifice that they set them into their armor for protection. In Islam, Garnets illuminate the fourth heaven, while for Norsemen, they guide the way to Valhalla. A Grimm’s fairy-tale even tells of an old lady, who upon rescuing an injured bird was rewarded for her kindness with a Garnet that glowed, illuminating the night.

A rare, natural cocktail primarily of Pyrope with traces of Spessartite, Umbalite was first unearthed in 1978 and named for the locale of its discovery. A variety of Garnet, Umbalite is also referred to as Malaia (Malaya), which means ‘outcast’ or ‘out of the family’ in Swahili (a language of Tanzania and Kenya), as they do not match the color and gemological properties of other better-known Garnets. Interestingly, Blue Garnet is composed of equal amounts of Pyrope and Spessartite. Vanadium (compared to chromium that causes color change in Alexandrite) and manganese are the main cause of color change in Umbalite, noting Blue Garnet contains a much higher vanadium component than typically encountered in Umbalite. January’s birthstone, Garnet’s name is derived from the Latin ‘granatus’ (from ‘granum’, which means ‘seed’) due to some Garnets’ resemblance to pomegranate seeds. Coming in blues, chocolates, greens, oranges, pinks, purples, reds and yellows, Garnets are a group of minerals possessing similar crystal structures, but varying in composition, giving each type different colors and properties.


‘Blue Garnet’ was first reported as ‘Blue-Green Pyrope-Spessartite Garnet with High Vanadium’ in the GIA’s (Gemological Institute of America), Gems & Gemology, Fall 2017, Vol. 53, No. 3. and hails from the Umba River (Umba Valley) in Tanzania’s Tanga Region close to the Kenyan border. Color Change Garnets’ notable deposits are Tanzania’s Umba Valley (1987), Bekily in southern Madagascar (late 90s) and most recently (January 2009), near the village of Kamtonga in Kenya’s Taita Taveta District.

A rare and unusual sub-variety of an already rare Garnet, despite its beauty, Blue Garnet will always be very limited, and not only dependent on the luck of miners scouring sporadic, small and ever depleting pockets of Color Change Umbalite Garnet, but also deft grading and selection post lapidary to ensure color consistency and quality. Due to their rarity and only available in small sizes, calibrated Blue Garnet for jewelry is extremely challenging to execute. Blue Garnet is also totally natural, which further increases its rarity.

Durability & Care

Blue Garnet (Mohs’ Hardness: 7 – 7.5) is an excellent choice for everyday jewelry. Blue Garnet should always be stored carefully to avoid scuffs and scratches. Clean with gentle soap and lukewarm water, scrubbing behind the gem with a very soft toothbrush as necessary. After cleaning, pat dry with a soft towel or chamois cloth.

Map Location

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