Difference between revisions of "Ammolite"

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Natural ammolite has a hardness of 3.5, but is most often sold as a doublet or triplet in order to protect the gem material.  Natural stones are often impregnated with an epoxy to strengthen the ammolite.<br />
 
Natural ammolite has a hardness of 3.5, but is most often sold as a doublet or triplet in order to protect the gem material.  Natural stones are often impregnated with an epoxy to strengthen the ammolite.<br />
 
Color comes from interference, and it is dependant on the thickness of the layers of aragonite.  From thickest to thinnest: red, green, blue, purple<br />
 
Color comes from interference, and it is dependant on the thickness of the layers of aragonite.  From thickest to thinnest: red, green, blue, purple<br />
The color play is a result of iridescence (diffraction).
+
The color play is a result of iridescence (interference).
  
 
==Sources==
 
==Sources==

Revision as of 08:47, 16 December 2006

Ammolite
Chemical composition CaC03 with trace elements
Crystal system Orthorhombic
Habit Fractured and non-fractured flat layers
Fracture Parting along layers
Hardness 3.5
Refractive index 1.525 - 1.670
Birefringence 0.135 - 0.145
Specific gravity 2.60 - 2.85
Lustre Vitreous to resinous

Ammolite is an organic gemstone that is mined in Southern Alberta, Canada.
Natural ammolite has a hardness of 3.5, but is most often sold as a doublet or triplet in order to protect the gem material. Natural stones are often impregnated with an epoxy to strengthen the ammolite.
Color comes from interference, and it is dependant on the thickness of the layers of aragonite. From thickest to thinnest: red, green, blue, purple
The color play is a result of iridescence (interference).

Sources

  • Ammolite: Iridescent Fossilized Ammonite .. - Keith A. Mychaluk et all.- Gems & Gemology (Spring 2001)

External links