Vivianite Value, Price, and Jewelry Information

Rectangle-cut vivianite, 0.95 cts, 8.8 x 4.8, Bolivia. © The Gem Trader. Used with permission.

Vivianite

Vivianite is so fragile and soft, any faceted gems would be difficult to handle safely, let alone wear. Nevertheless, its blue and green colors are so rich, a few stones (very few) have been cut. Vivianites make beautiful collector’s gemstones.

Vivianite Information

Data Value
Name Vivianite
Colors Colorless (fresh); darkens to shades of green and blue, then dark green, dark bluish green, dark purplish, bluish black.
Crystallography Monoclinic. Crystals prismatic, tabular, equant; in clusters, radial groups. Also massive, bladed, fibrous; crusts, earthy masses.
Refractive Index 1.569-1.675
Luster Vitreous, pearly on cleavage; also dull, earthy.
Hardness 1.5-2
Wearability Poor
Fracture Fibrous
Specific Gravity 2.64-2.68
Birefringence 0.040-0.059
Cleavage Perfect 1 direction
Dispersion Weak
Luminescence None.
Luminescence Present No
Transparency Transparent to opaque
Absorption Spectrum Not diagnostic.
Identifying Characteristics Color darkens in light.
Formula

Fe3(PO4)2 · 8H2O.

Pleochroism

Intense: blue/pale yellowish green/pale yellowish green; or deep blue/pale bluish green/pale yellow green; or indigo/yellowish green/yellowish olive-green.

Optics

a = 1.569-1.516; β = 1.602-1.656; γ = 1.629-1.675. Biaxial (+) 2V = 63-83°.

Optic Sign Biaxial +
Etymology

After J. H. Vivian, the English mineralogist who discovered the species.

Occurrence

A secondary mineral in ore veins. Also occurs as an alteration product of primary phosphate minerals in granite pegmatites; forms as sedimentary concretions.

vivianite - Morococala Mine

Three lustrous, deep green vivianites from the Morococala Mine, Santa Fe Mining District, Oruro Department, Bolivia. © Rob Lavinsky, www.iRocks.com. Used with permission.

Comments

In an interview, rare gem faceter and supplier C. D. Parsons acknowledges looking forward to cutting vivianite someday, something very few have done. With a hardness between talc and gypsum and perfect cleavage, few could facet this stone. Thin pieces are even flexible and sectile (cuttable with a knife).

However, this gem material can show beautiful dark shades of blue and green. It also displays intense pleochroism. Depending on the viewing angle, stones can reveal up to three colors, including yellowish green and olive-green, blue-green, and indigo.

vivianite - Huanuni Mine

Vivianite crystal, Huanuni Mine, Huanuni, Dalence Province, Oruro Department, Bolivia. Photo by Géry Parent. Licensed under CC By-SA 3.0.

Is There Vivianite in Odontolite?

In the past, vivianite was believed to be the cause of the blue color of so-called odontolite. This fossilized bone and teeth material may resemble turquoise. (It’s also called “bone turquoise”). However, heat treatments have been shown to produce the color artificially.

Identifying Characteristics

When mined, vivianites are colorless or pale green, but their colors darken after exposure to light. As a result, an enthusiast may find an attractive color disappearing over time. Not surprisingly, this further de-incentivizes cutting an already challenging stone. Still, the appeal remains.

Like its coloration, vivianite’s streak starts colorless but becomes dark blue over time. Please note: don’t conduct streak testing on finished gems. Test material in inconspicuous spots as a last resort only.

Bolivian material has the following properties.

Synthetics

Scientists have synthesized vivianite for a variety of purposes, including environmental and agricultural research. However, there’s no known jewelry use for this lab-created material.

Enhancements

No known gemstone treatments or enhancements.

Sources

These sources yield good-quality gem material:

  • Bolivia, Llallagua and Poopo: fine, cuttable crystals to 6 inches long.
  • Cameroon, N’gaoundere: massive crystals up to 4 feet long, dark in color, cuttable.
  • United States: Lemhi County, Idaho, fine crystals; Richmond, Virginia, good crystals; Bingham Canyon, Utah, crystals to 5 inches in length.

Other notable sources include the following locations:

  • United States: California; Colorado; Delaware; Florida; Maryland; New Jersey; Black Hills, South Dakota (in pegmatites).
  • Australia; Canada; England; France; Germany; Japan; Russia.
vivianite - Germany

An unusual specimen of radiating, intergrown blade-shaped vivianites. Hesse, Germany. © Rob Lavinsky, www.iRocks.com. Used with permission.

Stone Sizes

Gem cutters rarely facet vivianites, and their almost micaceous cleavage makes polishing gems very difficult. For example, the Bolivian material could yield cut stones up to 75-100 carats. However, this just doesn’t occur.

Care

Due to its fragility, this gem material would make an improbable jewelry stone. Store your vivianite specimens out of the light to protect their color. Consult our gemstone jewelry cleaning guide for more recommendations.

vivianite - Florida

Glassy, blue-green vivianites on matrix from Clear Springs Mine, Bartow, Polk County, Florida, USA. © Rob Lavinsky, www.iRocks.com. Used with permission.