Shattuckite Value, Price, and Jewelry Information

Locality: Mesopotamia 504, Copper Valley, Khorixas, Damaraland District, Kunene Region, Namibia (Locality at mindat.org) Size: 2.9 x 2.6 x 2.1 cm. Shattuckite is very rare in crystalline form. This new find from the area of Khorixas, in a remote part of Namibia known for scheelite in the past, is surprising. This is a superb specimen with a rich carpeting of beautiful crystals. By Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC-BY-SA-3.0], via Wikimedia Commons

Shattuckite

Shattuckite Value

Highest values go to finer blue colors.

The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.

Shattuckite Information

Data Value
Name Shattuckite
Stone Sizes Only cabochons can be cut, up to several inches in length.
Formula Cu§(Si01)4(OH)2.
Colors Blue of various shades.
Fracture Uneven to splintery
Hardness 3.5
Cleavage Very good in 2 directions
Crystallography Orthorhombic. Crystals slender prismatic; massive, granular; fibrous.
Refractive Index 1.752-1.815
Birefringence 0.063
Luminescence None.
Luminescence Present No
Absorption Spectrum Not diagnostic.
Pleochroism None.
Optics a = 1.752-1.753; β = 1.782; γ = 1.815. Mean refractive index 1.75. Biaxial (+), 2V = 88°.
Optic Sign Biaxial +
Luster Vitreous to silky.
Polish Luster Vitreous to silky.
Specific Gravity 3.8-4.11
Transparency Translucent to opaque.

Optics

a = 1.752-1.753; β= 1.782; γ=1.815. Mean refractive index 1.75.

Biaxial (+), 2V: 88°.

Occurrence

An alteration product of secondary copper minerals.

  • Shattuck Mine, Bisbee, Arizona: dense blue massive material; also psuedomorphous after malachite.
  • Ajo, Arizona: with other copper minerals.
  • Katanga, Zaire: masses of light blue crystals; fibrous, radial aggregates, sometimes resembling a pale blue pectolite.

Comments by Dr. Joel Arem

Shattuckite is often mixed with quartz, and data often reported for properties may be erroneous. The cabochons are rich blue in color and very popular, but the material is not abundant and seldom seen on the market.

Comments by Donald Clark, CSM IMG

Often mixed with quartz. Primary source Shattuck Mine, Bisbee Arizona.

Shattuckite is often confused with plancheite, which has recently been identified as a separate species, formula Cu8(Si4O11)2(OH)4 . xH20 There is no method of distinguishing between these species with common instruments. Gems must be sent to a major lab for positive identification.

Name

From the Arizona locality, the Shattuck Mine. Recent studies have shown that plancheite, a mineral similar to and often confused with shattuckite, is a distinct species. The formula of plancheite is: Cu8(Si4O11)2(OH)4 ·Xh2O.

by Joel E. Arem, Ph.D., FGA, Donald Clark, CSM IMG