Crystal of bicolor spodumene var. kunzite Kunzite-Nouristan Spodumene

Spodumene is a pyroxene member of inosilicate mineral with chemical formula is LiAl(SiO3)2, lithium aluminium. It can also be pink, lilac, or green. Crystals are prismatic, flattened, and typically striated along their length. Gem varieties of the mineral usually exhibit strong pleochroism. Spodumene is an important  ore of lithium. It occurs in lithium-bearing granite pegmatite dykes, often with other lithiumbearing minerals, such as eucryptite and lepidolite. One of the largest single crystals of any mineral ever found was a spodumene specimen from South Dakota, USA, 47 ft (14.3 m) long and 90 tons in weight.

With competitive price and timely delivery, Yayang sincerely hope to be your supplier and partner.

Ordinary low temperature form α-spodumen is found in the monoclinic system, while high-temperature β-spodumen crystallizes in the tetragonal apparatus. Ordinary α-spodumen is converted to β-spodumen at temperatures above 900 ° C. The crystals are generally densely streaked parallel to the main axis. Crystal faces are usually scraped and pitted with triangular markings. (Wiki)

Name: From the Greek for ash-colored, in allusion to its color.

Association: Quartz, albite, petalite, eucryptite, lepidolite, beryl

Mineral Group: Pyroxene group

Chemical Properties

Chemical Classification Inosilicate Formula LiAl(SiO3)2 Common Impurities Fe,Mn,Mg,Ca,Na,K,H2O

Spodumene Physical Properties

Crystal habit prismatic, generally flattened and elongated, striated parallel to {100}, commonly massive Color Colourless, yellow, light green, emerald-green, pink to violet, purple, white, gray Streak White Luster Vitreous, Dull Cleavage Perfect Diaphaneity Transparent, Translucent Mohs Hardness 6,5 &#; 7 Crystal System Monoclinic Tenacity Brittle Density 3.03&#;3.23 Fracture Uneven to subconchoidal Other characteristics Tenebrescence, chatoyancy, kunzite often fluorescent under UV (Wikipedia) Fusibility         3.5 Solubility         Insoluble

Spodumene Optical Properties

Color / Pleochroism Strong in kunzite: α-purple, γ-colorless; hiddenite: α-green, γ-colorless 2V: Measured: 54° to 69°, Calculated: 88° RI values: nα = 1.648 &#; 1.661 nβ = 1.655 &#; 1.670 nγ = 1.662 &#; 1.679 Twinning Common on {100} Optic Sign Biaxial (+) Birefringence δ = 0.014 &#; 0.018 Relief Moderate Dispersion: weak

Occurrence of Spodumene

Spodumen occurs in lithium-rich granite pegmatites, aplites and gneisses. Related minerals are: quartz, albite, petalite, eucryptite, lepidolite and beryl.

The obvious material has been used as a precious stone with its kunzite and hiddenite varieties which have attracted attention with their robust pleochroism for a long time. Resource locations include Afghanistan, Australia, Brazil, Madagascar, Pakistan, Quebec in Canada, and North Carolina, California in the USA.

Uses Area and Economic Importance

Spodumene is an essential supply of lithium to be used in ceramics, cell phones and car batteries, medicine, Pyroceram and as a fluent substance. it&#;s far extracted from spodumene with the aid of fusing in lithium acid.

World lithium production through spodumen is approximately 80,000 mt per year, mainly from the Greenbushes pegmatite of Western Australia and some Chinese and Chilean sources. The Talison mine at Greenbushes in Western Australia is reported to be the largest and the highest ore level at 2.4% Li2O ( figures).

Another important advantage that the spoiler has over the more popular saltwater competitors is the purity of the lithium carbonate it can produce. While all products used by the battery industry are at least 99.5% lithium carbonate, the formation of the remaining 0.5% is important; High amounts of iron, magnesium or other harmful materials make the brine less attractive product.

Gemstone Varieties

Hiddenite: The emerald green spodümen type is colored with chromium like emerald. Not all green spodumens are tinted with chrome, which tends to have a lighter color and is therefore not hidden.

Kunzite: Kunzite is a colorful gemstone that changes from pink to lilac, with a small amount of trace color and various spodumens of manganese colors. Some (not all) used for gemstones are heated to increase the color of kunzite. Also, it is irradiated frequently to improve color.

Triphane: Triphane is a yellow Spodumene variety.

Distribution

• From Uto, Sodermanland, and in the Varutrask pegmatite, 15 km northwest of Skelleftea, Vasterbotten, Sweden.
• In Finland, from near Kuortane, and in the Tammela district.
• In the USA, giant crystals in the Etta mine, near Keystone, Pennington Co., and elsewhere in the Black Hills, South Dakota; at Hiddenite, Alexander Co. and in the Foote mine, Kings Mountain, Cleveland Co., North Carolina; from the Pala district, San Diego Co., California; and in the Harding mine, Dixon, Taos Co., New Mexico.
• From the Tanco mine, Bernic Lake, Manitoba, Canada.
• At the Urupuca mine, Itambacari, and at Resplendor, Minas Gerais, Brazil.
• From Mawi and Kantiva, Nuristan district, Laghman Province, Afghanistan.
• At Maharitra, Mt. Bity, and at Anjanabonoina, Madagascar.
• From Bikita, Zimbabwe. Many other minor localities are known.

References

• Bonewitz, R. (). Rocks and minerals. 2nd ed. London: DK Publishing.
• Dana, J. D. (). Manual of Mineralogy&#; Wiley.
• Handbook of Mineralogy. [online] Available at: http://www.handbookofmineralogy.org [Accessed 4 Mar. ].
• Mineral information, data and localities.. [online] Available at: https://www.mindat.org/ [Accessed. ].
• Wikipedia contributors. (, March 21). Spodumene. In Wikipedia, The Free Encyclopedia. Retrieved 23:32, July 7, , from https://en.wikipedia.org/w/index.php?title=Spodumene&oldid=

Home » Minerals » Spodumene

Spodumene

An important source of high-purity lithium and a gemstone with collector appeal

Article by: Hobart M. King, PhD, RPG

What is Spodumene?

Spodumene is a pyroxene mineral that is typically found in lithium-rich pegmatites. It is usually associated with other lithium minerals such as lepidolite, eucryptite, and petalite. Spodumene has a chemical composition of LiAlSi2O6 but small amounts of sodium sometimes substitute for lithium.

For more information, please visit Dolomite Powder.

Throughout most of the 20th century, spodumene was the most important ore of lithium metal. Lithium brines discovered in South America and other locations have become a more important source of lithium metal.

Spodumene is also used as a gemstone, and in that use the color variety names of the mineral are used. Pink to purple spodumene is known as kunzite, green spodumene is known as hiddenite, and yellow spodumene is known as triphane.

The perfect cleavage of spodumene makes it a fragile gem for use in rings and any jewelry that might be exposed to abrasion and impact. It is considered a &#;collector gem&#; by some gemologists.

ADVERTISEMENT

Enormous Crystals

Spodumene often occurs in extremely large crystals. One of the earliest accounts of large spodumene crystals is from the Etta Mines, Black Hills, Pennington County, South Dakota. The United States Geological Survey, Bulletin 610 reports:

"The crystals are often of enormous size. In the Etta Mine, where they are best exposed both in the open cut and tunnel, they frequently attain a diameter of 3 to 4 feet and a length of 30 feet. The largest "log" so far found was 42 feet long and 5 feet 4 inches in maximum diameter. This one log alone would yield 90 tons of spodumene." [1]

Physical Properties of Spodumene

Chemical Classification Silicate Color White, gray, colorless, yellow, green, blue, lilac, pink, brown. Sometimes pleochroic Streak White, colorless Luster Vitreous, pearly Diaphaneity Transparent to translucent Cleavage Perfect in two directions with parting Mohs Hardness 6.5 to 7 Specific Gravity 3.1 to 3.3 Diagnostic Properties Prismatic crystals with strong striations parallel to their principal axis. Perfect cleavage. Chemical Composition LiAl(SiO3)2 Crystal System Monoclinic Uses Gemstones (kunzite, hiddenite, triphane). Once the most important source of lithium metal.

Spodumene as an Ore of Lithium

Spodumene once served as the most important ore of lithium metal. It was very costly to liberate lithium from the silicate mineral; however, lithium refined from spodumene was of very high purity. In the late s, subsurface brines with high concentrations of lithium were developed in Argentina, Chile, China and other locations. These brines could be pumped to the surface, allowed to evaporate, and lithium was easily processed from the evaporite material.

As lithium-rich brine deposits were developed, the more costly use of spodumene as an ore of lithium declined. At times, the demand for lithium has exceeded what can be produced from working brine deposits. In those times spodumene can become an important source of lithium metal.

Spodumene as a Gemstone

Spodumene sometimes occurs in transparent crystals in pastel shades of pink, purple, green, and yellow. These have been cut into gemstones that are prized by collectors. However, their use in jewelry is limited to pieces that will be subject to limited abuse because of spodumene's perfect cleavage.

ADVERTISEMENT

Kunzite

Pink to lilac specimens of gem-quality spodumene are highly prized and known as "kunzite". The color of these specimens is attributed to the presence of manganese as a chromophore. Kunzite is the most commonly encountered spodumene gem.

Many specimens of kunzite are strongly pleochroic, with the deepest color observed when the gem is viewed down the principal axis. To take full advantage of this phenomenon, gemstones are usually cut with their tables perpendicular to the principal axis to yield stones of the deepest color.

Hiddenite

Emerald-green spodumene is known as "Hiddenite." Its vivid green color is very similar to emerald and is attributed to the presence of chromium as a chromophore. It is the rarest gem variety of spodumene. It was first found near the town of White Plains, North Carolina, which changed its name to "Hiddenite" after the popular gemstone that attracted people to the area.

Triphane

Spodumene rarely occurs in a yellow color. However, some yellow spodumene can be of gem quality, and it has been cut into faceted and cabochon gems. These gems have been given the name &#;triphane&#;.

It should be noted that &#;triphane&#; is one of the early names used for spodumene. It can be encountered in mineralogical writings from the s and early s. Any use of the word &#;triphane&#; from that era is referring to spodumene as a mineral because gemological use of the word did not begin until the late s.

ADVERTISEMENT

Treatment of Gem-Quality Spodumene

Some gem-quality spodumene will develop a richer color when heated or irradiated. These procedures have been applied to many gems that enter the marketplace. Some of these will fade over time when exposed to direct sunlight. Valuable spodumene gems of any color should be stored away from direct light.

Did You Know? Lithium is an active ingredient in some medications. Salts of lithium are used in medication for bipolar disorder. The lithium contributes to a "mood-stabilizing" effect. One product has been named "Lithium." Image copyright iStockphoto / Paige Foster.

Demand for Spodumene

The demand for spodumene is dependent upon the use of lithium in manufacturing. In the past, most lithium compounds and minerals were used to produce ceramics, glass, aluminum alloys, and high-temperature grease. However, in the last two decades an exploding demand for rechargeable batteries to power vehicles, cell phones, tablet computers, cameras, music players, GPS units, and other portable electronic devices is driving the demand for high-purity lithium - and that drives the demand for spodumene.

Lithium batteries have a much higher charge-to-weight ratio and power-to-weight ratio than lead/acid and zinc carbon cells. This has increased the demand for lithium as a battery metal. However, the use of batteries to power vehicles has resulted in an enormous amount of research related to battery metals. It is possible that lithium could be replaced by another battery metal such as cobalt.

Spodumene Information [1] Mineralogic Notes, Series 3: Waldemar Schaller, Gigantic Crystals of Spodumene, United States Geological Survey, Bulletin 610, .

[2] Lithium: Brian W. Jaskula, United States Geological Survey, Mineral Commodity Summaries, January .

[3] Lithium: Brian W. Jaskula, United States Geological Survey, Minerals Yearbook, September .