Kämmererite Value, Price, and Jewelry Information

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Kämmererite (individual crystals average 5 mm across; specimen measures 8.7 x 5.4 x 4.2 cm), Kop Krom mine, Kop Daglari, Erzurum Province, Turkey. © Rob Lavinsky, www.iRocks.com. Used with permission.

A beautiful but rare mineral, kämmererite is extraordinarily difficult to facet. As a result, the availability of cut gems is severely limited. A few clean, well-cut gems do exist — a testimony to the perseverance of hobbyists!

Kämmererite Information

Data Value
Name Kämmererite
Is a Variety of Clinochlore
Colors Red to purplish red, cranberry red.
Hardness 2-2.5
Fracture Micaceous
Cleavage Perfect basal cleavage
Formula (Mg,Cr)6(AISi3)O10(OH)8 (Chlorite Group).
Crystallography Monoclinic; crystals hexagonal shape, bounded by steep sided pyramids.
Refractive Index 1.597-1.600
Birefringence 0.003
Luminescence None reported
Luminescence Present No
Absorption Spectrum Not diagnostic
Pleochroism Strong: violet/hyacinth-red.
Optics = 1.597; β = 1.598; γ = 1.599-1.600. Biaxial; optic sign variable.
Optic Sign Biaxial +, Biaxial -
Luster Vitreous; pearly on cleavages.
Specific Gravity 2.64
Transparency Translucent to transparent
Etymology Named after August Alexander Kämmerer, chief chemist and mining director at St. Petersburg, Russia (1789-1858).
Occurrence In chromite deposits, associated with clinochlore and uvarovite.
Kämmererite crystals

Kämmererite crystals, Kop Krom mine, Kop Daglari, Erzurum Province, Eastern Anatolia Region, Turkey. Photo by Didier Descouens. Licensed under CC By-3.0.

Comments

A chromium-bearing (Cr) variety of clinochlore, kämmererite shows red to purplish red colors. All clinochlores belong to the chlorite group. Of these minerals, faceters have only rarely cut kämmererites and sheridanites as gemstones.

However, cutting kämmererites isn’t easy, because this material is micaceous. It will easily separate into thin sheets or layers known as laminae, which actually have a flexible tenacity. Kämmererites also have perfect basal cleavage, so they have a tendency to split when struck. Adventurous faceters would have to handle these stones with great care.

Gemstone aficionados would have to be even more adventurous to wear finished kämmererites as jewelry stones. They have a hardness of just 2 to 2.5. If you wore a kämmererite ring, a copper coin in a pocket or purse would scratch the gem. A more pervasive hazard, household dust (with a hardness of 7) would scratch it even more easily.

In mineralogical references, you may find these stones referred to as chromium-bearing clinochlores rather than kämmererites. Nevertheless, “kämmererite” is an accepted name.

Identifying Characteristics

Kämmererites have a low birefringence (0.003), and faceted specimens may have a very poor polish due to their low hardness. As a result, some faceted specimens may appear to be singly refractive when examined with a refractometer. Use a polariscope or dichroscope to confirm if such a stone is actually doubly refractive.

Synthetics

No known synthetics or enhancements.

Sources

Turkey is the main source of facetable material. The province of Erzurum produces distinct crystals.

India has produced some material that has been cut into cabochons.

Other notable sources include the following:

  • Russia: Lake Itkul, near Miask.
  • United States: California; Pennsylvania; Texas.

Stone Sizes

Facetable material is quite rare and always small. Minute gems, 1-2 carats, have been cut from Turkish material.

Care

You’re more likely to find kämmererites in a mineral collection than a jewelry collection. Have a jeweler mount them in protective settings and reserve any jewelry pieces featuring these gems for occasional wear. Store them separately from other harder jewelry stones to prevent contact scratches.

Clean kämmererites only with a soft brush, mild detergent, and warm water. Consult our gemstone jewelry cleaning guide for more recommendations.

kämmererites

These kämmererite crystals, resting on a kämmererite matrix, may be cuttable, but they also make a beautiful mineral specimen. 2.1 x 1.3 x 1.1 cm, Kop Krom mine, Kop Daglari, Erzurum Province, Eastern Anatolia Region, Turkey. © Rob Lavinsky, www.iRocks.com. Used with permission.

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