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Spodumene is almost exclusively a pegmatiticmineral of the pyroxene group that forms inmonoclinic system with a chemical formula of

LiAlSi2O6. Its hardness is 6.5 to 7 on the Mohs’ scaleand displays perfect prismatic cleavage. Transparentand colored varieties show strong pleochroism.Strangely, the name spodumene means “ash-col-ored” in Greek referring to the dull and colorlessexamples when it was first named in the second halfof the 19th century.

In 1879, an exciting green and transparent variety ofspodumene was discovered. It was named hiddeniteafter its type locality Hidden, North Carolina. It is con-sidered to be the rarest of spodumene varieties andcolored by chromium. Gemologists must understandthat not all green spodumene from Hidden, NC ishiddenite. This is a misleading practice in the gemmarket which is sometimes extended to other greenand yellow spodumenes from other localities too. Atrue chromium colored hiddenite with a saturatedgreen color is extremely rare. There is also a yellowvariety called triphane.

George Fredrick Kunz, the legendary American min-eralogist-gemologist must have been very excitedwhen he first discovered a pink variety of spo-dumene as it had been known only in colorless andgreen. He and Charles Baskerville first publishedtheir findings of pink spodumene from Pala,California in 1903. Almost a year later, Mr. Baskervillenamed this variety as “Kunzite” in honor of G.F.Kunz. In his famous book of “The Curious Lore of

Precious Stones,” Mr. Kunz humbly suggests analternative birthstone’s list for Americans in 1913. Hewrites; “As it might seem appropriate that one bornin the United States should wear a gem from amongthose which our country furnishes, the following listwas sometime since prepared by the writer, not inany sense as a substitute for the real birth-stones,but as possible accessory gems (when they are notidentical), gems which might be worn from a spirit ofpatriotism.” In this list, kunzite is marked forSeptember and listed as found in California.

Kunzite’s subtle rosy color is in pink to purplish pinkrange and caused by manganese. Most stones dis-play very light tones so it is common to see them cutwith deep pavilions. Since the color is so light, small

KUNZITE:A ROSY SPODUMENE WITH

AN AMERICAN NAME...

Kunzite, 14.09 ct. Photo by Orasa Weldon.

Courtesy of Leslie Weinberg Designs.

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GEM FOCUS

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stones look almost colorless. Anicely colored faceted kunzitewith correct orientation would dis-play a medium purplish pink withan eye visible pleochroism.However, kunzite is like a delicaterose. Not only does its perfectcleavage pose a durability issuebut also its color may fade awayonce it is exposed to daylight,more specifically ultraviolet light.If the natural pink of kunzite isbleached via sunlight exposure, itmay be restored by irradiation, fol-lowed by heating at low tempera-tures of 100°C to 200°C toremove the green and sometimesbrown colors. It is also known thatsuch low temperatures are used to draw out thebluish tinge to produce more pink stones.Unfortunately, the irradiation of kunzite for color treat-ment cannot be detected.

Major gem quality producing localities include Brazil,Afghanistan, Madagascar alongside California. One ofthe largest faceted kunzites of the world is in theNational Gem Collection of the Smithsonian Institute.

This 880 carat heart shaped gemis from Brazil. Afghanistan isknown to produce fairly large kun-zite crystals too. In fact, a well-formed gemmy kunzite crystalattached to the matrix may beworth more as mineral specimenthan a faceted stone as long asthe locality is documented accu-rately.

Kunzite is a fairly affordable gem-stone and needs careful settingdue to its durability issues. Whilestones over 10 carat sizes mightbe sold around $150 per carat inextra fine category, the similarweights in commercial range can

go as low as $8 per carat at wholesale level. Sincethe treatment is not detectable, there is no price dif-ference can be applied. Kunzite is not known to besynthetically produced either. Any simulant can beseparated through conventional gem testing meth-ods easily. u

Photo in Heading: Kunzite 5.32 ct. Photo by Mia Dixon. Courtesy of Pala

International.

Kunzite from Afghanistan, 8.66 ct.Photo by Mia Dixon.

Courtesy of Pala International.