Scorodite Value, Price, and Jewelry Information

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Scorodite: Tsumeb, Namibia (1.0). Photo © Joel E. Arem, PhD, FGA. Used with permission.

With lovely colors and intense pleochroism, faceted scorodite is a prize for collectors of the rare and unusual. However, it’s too soft for jewelry use.

Scorodite Information

Data Value
Name Scorodite
Is a Variety of Variscite
Crystallography Orthorhombic. Crystals pyramidal, tabular, prismatic; massive, crusts.
Crystallographic Forms
Refractive Index Varies by locality, 1.738-1.816. See "Identifying Scorodites" below.
Colors Pale grayish green, yellowish brown to brown, colorless, blueish green, blue, violet.
Luster Vitreous to resinous
Hardness 3.5-4
Fracture Subconchoidal
Specific Gravity 3.28-3.29
Birefringence Varies by locality, 0.027-0.031. See "Identifying Scorodites" below.
Cleavage Imperfect
Dispersion Relatively strong
Luminescence None
Luminescence Present No
Transparency Translucent to semi-transparent
Absorption Spectrum One line at 4500, broad absorption in the green (Tsumeb).
Phenomena Color change (very rare)
Formula Fe3+AsO4 · 2H2O
Pleochroism Intense: purplish/bluish (Tsumeb).
Optics Biaxial (+), variable 2V. See "Identifying Scorodites" below.
Optic Sign Biaxial +
Etymology From the Greek skorodon for “garlic,” because the material emits the typical garlic odor of arsenic when heated.
Occurrence A secondary mineral resulting from the oxidation of arsenious ores.
scorodite - Portugal

Scorodite crystal, Alto das Quelhas do Gestoso Mines, Gestoso, Manhouce, São Pedro do Sul, Viseu District, Portugal. Picture width 1.5 mm. Collection and photograph of Christian Rewitzer. Licensed under CC By-SA 3.0.

What is Scorodite?

Scorodite belongs to the variscite mineral group. It forms series as the ferric iron analogue (Fe3+) with mansfieldite (AlAsO4 · 2H2O), yanomamite (InAsO4 · 2H2O), and strengite (FePO4 · 2H2O). These minerals occur far more rarely than their fellow series member scorodite. Accordingly, faceted examples of these minerals are even rarer than faceted scorodites.

faceted mansfieldite

Pear-cut mansfieldite, 2.99 cts, 12.6 x 7.8 mm, Algeria. © Rob Lavinsky, www.iRocks.com. Used with permission. (Images combined to show details).

Does Scorodite Make a Good Jewelry Stone?

Although not a rare mineral in nature, faceted or cabbed scorodites are extremely rare. A low Mohs hardness score of 3.5 to 4 and imperfect cleavage make them very susceptible to scratches and blows. Thus, scorodites just don’t have the wearability to serve as jewelry stones. Furthermore, they’re soluble in acids and contain arsenic. Gem cutters should take precautions to prevent inhaling particles, protect their eyes, and wash their hands while working with scorodites.

Since such a soft stone can be scratched easily, which can release small particles of the gem, jewelry use is not recommended. Reserve scorodites for display in mineral or gem collections.

scorodite cabochon - Morocco

Oval cabbed scorodite, 5.18 cts, 11.8 x 9.5 mm, Morocco. © The Gem Trader. Used with permission.

Identifying Scorodites

Rare specimens display color change, from blue-green in daylight to blueish purple or grayish blue in incandescent light.

Scorodites may have a greenish-white streak. Please note that streak testing may harm or destroy your specimen. Conduct it on a piece of rough, never a finished gem, only as a last resort.

Optical Properties of Scorodite from Various Localities

α

β

γ

Birefringence

2V

Durango, Mexico

1.784

1.795

1.814

0.030

75°

Idaho

1.738

1.742

1.765

0.027

60°

Oregon

1.741

1.744

1.768

0.027

40°

Tsumeb, Namibia

1.785

1.796

1.816

0.031

75°

Are There Synthetic Scorodites?

Scientists have synthesized scorodite, including crystals, for research into the safe disposal of arsenic. However, there is no known jewelry use of this material.

What is “Scorolite?”

Consumers may encounter so-called “scorolites” for sale online, especially as purplish beads. Occasionally, these same pieces are offered as a type of scorodite. More often, they’re marketed as “scorolite opals.” However, in fact, they’re simulants, usually purplish glass or quartz pieces. Of course, quartz and glass are distinct gemologically from opals and scorodites. Gemologists can readily distinguish these materials.

“Scorolite” is not an accepted synonym or trade name for scorodite. This confusion may stem from a typo in a paper on geo-environmental hazards in groundwater in India. Any gems sold as “scorolites” should come with a disclaimer identifying what they actually are.

scorolites

“Scorolite” rondelles. Photo courtesy of liveauctioneers.com and Blue Antiques Blue.

Enhancements

There are no known gemstone enhancements for scorodites.

Where is Scorodite Found?

Tsumeb, Namibia produces beautiful, pleochroic blue/purplish crystals, some gemmy, up to 25 mm long.

Durango, Mexico and Ouro Preto, Minas Gerais, Brazil also yield fine, blue crystals, some gemmy.

Other notable crystal sources include

  • United States: California; Idaho; Nevada; Oregon; South Dakota; Utah; Washington; Wyoming.
  • Algeria; Ontario, Canada; China; Japan; Morocco; Portugal; United Kingdom.
stalactitic scorodite - Algeria

An unusual stalactitic growth of scorodites. 7.7 x 6.2 x 1.0 cm, Djebel Debar, Hamman, Meskhootine, Constantine Province, Algeria. © Rob Lavinsky, www.iRocks.com. Used with permission.

Stone Sizes

Scorodites almost always make small faceted gems. As a reasonable maximum, expect about five carats. However, even that would be very large for the species.

  • Smithsonian Institution (Washington, DC): 2.6 (purplish, Namibia).

Scorodite Care

Clean scorodites with a soft brush, mild detergent, and warm water. For more care recommendations, consult our gemstone jewelry care guide.

scorodites

Scorodites: Tsumeb, Namibia (1.15, 1.50). Photo © Joel E. Arem, PhD, FGA. Used with permission.

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